Bit depth |
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The number of bits which are used to store each pixel in an image. Each additional bit adds twice as many color combinations to the number available. 1 bit (bit-mapped - monochrome), 8bit (indexed color and web-safe color), 16 bit (?thousands of colors?) and 24 bit (?true color?, ?millions of colors?) are common bit depths. Increasing the bit depth can greatly affect the quality and size of your images. |
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See Also
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Process color |
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Process color refers to the inks and process used when a wide range of colors are reproduced using a limited number of inks. CMYK is the most common process ink set. Cyan, Magenta, Yellow, and black(Key) inks are combined in varying amounts to produce a reasonably wide range of colors. This is much cheaper than using a different ink for every color required and in the case of continuous-tone images like photographs, makes printing in color possible. |
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See Also
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CHROMiX ColorNews Issue #14 - Color Management Myths 16-20 |
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Welcome to ColorNews, a periodic update on things related to Color Management. We are striving for a regular consistent newsletter of high value to our customers. Please let us know what your interests are so we can address these concerns in our coming issues. ============================================================= C H R O M i X C O L O R N E W S
Issue #14 =============================================================
** There are TWO AUGUST ONLY SPECIALS from GretagMacbeth to note: ** Monaco's $50-$75 Rebate for Optix XR and Optix XR Pro ends at the end of August. If you've thought about pulling the trigger on this fine monitor calibration product, now is the time. Se ad below. ** For a limited time, CHROMiX is launching our new "Buy it Back" trade-in program. CHROMiX will buy your old competitive monitor calibration device when purchasing Eye-One profiling solutions. We'll pay you $80 when you buy an Eye-One Display and $200 when you buy an Eye-One Photo, Publish or Beamer. Contact Sales for more information. ** The transition of ProfileCity into CHROMiX is continuing to prove to be a success. However, some of you have had questions about the difference between the two services. Please read below for the answers to this question. ** 'Five more Color Management Myths', an article written by CHROMiX President Steve Upton that you'll want to read. ==================================================================== Table of Contents =================
1. CHROMiX News
CHROMiX News ================ Since our last ColorNews Issue #13 (June 15, 2004) many things have happened at CHROMiX that are worth mentioning:
We are continuing the WebEx training series. By popular request, the next session will be "Color Management in Photoshop" conducted by Anne Taylor and will be held September 9th. When you register, please specify your time preference (11:00am or 1:30PM P.S.T). The cost is $129 each for up to 4 people plus $50 for the WebEx session.
CHROMiX has been chosen as a reseller of GATF products. Now you can buy any GATF testforms, books, videos, CDs, process controls and more from the CHROMiX ColorGear.com store. We're excited to be able to offer these great products at our typically low prices. Naturally, partners linking customers to us for these forms will share in the revenue. We'll integrate these items soon, but if you have any special request for GATF products, please let us know.
CHROMiX's integration of ICS's ProfileCity custom profiling operations has gone very well. However, some people have had questions about the differences in profiles made from either ColorValet or ProfileCity. Here are some answers: 1) CHROMiX personnel make ALL profiles. 2) The $99 profile from either is a one-step process (you print the target, we make the profile from the target). 3) The $199 ProfileCity profile is a two-step process (you print a linearization target and send it to us. From this we make and send you a custom profiling target that is optimized for your specific printer. You then print this and send to us). Does that help?
If you're an organization, association, manufacturer or large end user, give us a call to discuss how we can customize a profiling program to meet your company's and your customers' needs.
We get unsolicited positive reviews from our customers frequently. Most often we smile internally and pat ourselves on the back. In this case, we feel obligated to share this particular review, well, because it hit's the mark so well (and it was posted by some of our esteemed colleagues on an independent forum).
Have you ever thought about providing color management solutions but the opportunity was never quite right? Partner with CHROMiX! And we have a program just for your situation.
A bit of international travel for Steve this time around.
Mexico - Sept 4th, 2004 - ColorCorrecto is a color management conference which started in 2003 and is similar to the comprehensive GATF Color Management Conference held every December in Phoenix. Steve Upton, Don Hutcheson, Dave Hunter, Lou Prestia and others will be presenting during the conference which is help 2 hours North of Mexico City on Sept 2-5th 2004. Steve will be presenting three times on Sept 4 on Workflow, Myths and Realities of Color Management (big surprise!) and Spot color issues. Contact us at CHROMiX for more details.
London, England - Sept 28, 2004 - Steve finally gets to return to England after much too long an absence. Neil Barstow (Neil Barstow Consulting, UK) and Steve will be presenting at Apple London (near Heathrow). Called "Great Prints and Accurate Proofs: Gaining a better understanding of colour workflow" the seminar is approx 1/2 day in length and will include a valuable Print Reference Kit. We are working on a registration link, in the meantime please send an email to
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Color, Product & Industry News
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- Last issue we mentioned the possibility of an upcoming new product from X-Rite, the Pulse ColorElite. It's official: X-Rite has officially announced it! The New Pulse Color Elite Color Management System For Professional Photographers is designed form the ground up to offer professional photographers a color management solution that's easy to use, yet sophisticated and completely adaptive to any workflow.
- Canto Releases Cumulus Photo Suite August 1st, 2004. Version 6.0.3 has new options which offers efficient management of RAW image formats and improved IPTC support with IPTC editor. The IPTC editor lets users manage RAW image files from a wide array of digital cameras. Cumulus Photo Suite comprises the Cumulus Digital Camera RAW Filter and features the IPTC Information Window. When cataloging RAW image files, the Cumulus Digital Camera RAW Filter reads and interprets metadata from these images. The RAW Filter can capture metadata from different RAW image formats defined by the nine leading camera manufacturers, namely, Canon, Fuji, Kodak, Minolta, Nikon, Olympus, Sigma, Sinar and Sony. Photo Suite also supports Canon THM files with the Canon RAW Metadata Support module. Other information captured when cataloging include EXIF information (camera settings, shutter speed etc.) and, depending on the camera model, annotations and GPS as well. Users can also get excellent previews of cataloged RAW images easily. The user can select previews of stored thumbnails or RAW files. The filter settings for Color Interpolation can be set to obtain previews of varying quality and clarity.
- ColorVision is offering a $30 customer mail-in rebate for SpyderPRO until September 30, 2004. See details at
- Good news folks!
New orders for manufactured goods in June increased $2.7 billion or 0.7 percent to $363.2 billion, the Department of Commerce, Census Bureau reported today. This followed a 0.4 percent May increase.
- Further GOOD news!
- And according to Dr. Joe Webb, a writer and commentator for 'What They Think':
TECH NOTES
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RE: ColorEyes Digital Camera Profiling Solution
Some ColorEyes users were experiencing clipped and or blue shifted highlights in values from 240-255. In particular, wedding photographers were finding the clipping a problem. Since the target white is a luminance of 92, the software has to establish how to handle any values the camera captures above 92 without any data. Integrated Color did extensive testing to retool how ColorEyes handles tonal values above 240. The new version of ColorEyes which is a free upgrade for all existing users, now maintains the exact values the camera captures from 240-255 without any clipping or color shifts.
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CHROMiX ColorNews articles are a useful resource for technical information. In every issue are Tech Notes (above) and an article (below FAQ) that usually covers a technical topic of merit to users. ColorNews articles are archived and available for your FREE access at
SHOWS & EVENTS
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August 16-19 , Seybold San Francisco, 'From Concept to Reality', Moscone West, San Francisco, CA. Seybold SF introduces a newly reformatted conference program that focuses on continuing education for professionals in the four key aspects of content creation and publishing: Creating content, Publishing content, Marketing content and Managing content.
September 1-3, Photoshop World Conference and Expo, Orange County Convention Center, Orlando, FL. This event is the annual convention of the National Association of Photoshop Professionals (NAPP) and is aimed at graphic designers, photographers, Web designers, educators, print shops, ad agencies, publications, multi-media designers, service bureaus, art directors, motion graphics designers, and anyone who wants to stay on top of all the latest Photoshop techniques and technology.
October 10 - 13, 2004 GRAPH EXPO and CONVERTING EXPO at McCormick Place
October 24 28, 2004, XPLOR 2004, 25th Global Electronic Document Systems Conference & Exhibition at Dallas Convention Center, Dallas, TX.
December 5-7, 2004, the GATF 6th Annual Color Management Conference has been announced and will be held at the Hilton Pointe Mountain Tapatio Cliffs Resort. Steve Upton has been asked to serve on the board of directors this year and will be speaking in several sessions and Labs. More details to come.
January 10 - 14, MacWorld San Francisco, CA. Everything for the Mac devoted. West Coast style.
March 17-19, 2005 Graphic Arts 2005. Charlotte Convention Center, NC. This recent trade show and conference brought in thousands of industry professionals from the Southern USA. View the many highlights of the 2003 show edition and sign up to be reminded of the next show in Charlotte, NC.
September 9-15, 2005 PRINT '05 at McCormick Place Complex, Chicago, IL Because of its mammoth size and international presence, PRINT occurs only every four years and will take the place of GRAPH EXPO and CONVERTING EXPO in 2005.
ColorFAQ - Five more Color Management Myths
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ColorMyths 16-20 - again, there seems to be no end to these.
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First let's talk about 5000K, D50, D65, etc, how they are specified and what they describe.
5000K is a color temperature. It's a color of white that is based on heating a "black body" object to 5000 Kelvin. When you get something this hot it glows a yellowish-white. This color is expressed as a colorimetric number, such as XYZ, Yxy or Lab and is then called a correlated color temperature. The lights that produce these colors of white are not actually burning at that temperature, they just make the same color of light as a black body that is - that's the correlation.
D50, D65, etc are daylight illuminant standards based on spectral curves.
Remember, spectral curves are the most detailed light information we can get. When we add human observer influence we get colorimetric numbers. An important thing to realize is that many different spectral curves can result in the same colorimetric number. Another way of putting this is to say that fluorescent, incandescent and sunlight can all have significantly different spectral output but still produce the same color of white for a human observer; the same colorimetric number.
This "match" is for an even white card that has no brighteners. As each of these light sources have a different spectral make-up they will affect papers containing brighteners and printed colors differently.
The net effect of this is that two bulbs that measure as 5000K can affect paper and printed color differently and that one print can look different under two 5000K bulbs.
There is another measurement that reflects how closely a light source matches the D50 daylight spectral curve. CRI, the Color Rendering Index is expressed as a value out of 100. 100 is a perfect match to a reference light source that is within 100K temperature (D50 in the case of standard viewing environments). Typical cool white fluorescent bulbs have a CRI of about 62. The CIE states that the color differences between sources that differ by 3 CRI units is not perceptible. You should aim for CRIs that are as high as possible (over 95) when shopping for lighting and viewing products - and the booth can affect it as well.
I suppose the summary point of this myth is that 5000K is not a guarantee that you have a good light source or that it will match another 5000K light source effectively.
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D50, as mentioned above, is a standard daylight spectral curve.
This spectral information is defined very specifically using more than 30 curve points. It has a single colorimetric number and, unlike 5000K, it cannot be created by different light sources composed of different spectral output.
D50 is so specific in fact, that the only thing that can create it is the sun as it passes through the Earth's atmosphere.
Why choose a standard like D50 as an aim point if nothing man-made can achieve it? Well, because our visual system is based on millions of years of evolution under the sun. We are tuned to see objects illuminated by our star and filtered by our atmosphere.
The light source that I have seen to be the closest to D50 is the Solux lamp designed by Tailored Lighting. It is a Halogen light that can be easily mounted in track-lighting systems and is also quite inexpensive (around $9 US per bulb). The Solux CRI is 98, the industry's best. You can find out more information about these bulbs from
If you are not interested in the more "do it yourself" side of lighting that track-lighting sometimes requires, consider GTI or Just Normlicht light boxes. They are fluorescent-based lighting systems which may not have as high a CRI but they are so widely used (especially GTI in the US) that they are de facto standards themselves. If you want to view things as many others view them, light booths will typically get you there.
So, if a company is calling their lighting D50 I'd love to hear about it because it's probably not true. If they are calling it 5000K then they've chosen the broad side of a barn as their target. And if they quote a CRI they may be closer. At least they're more savvy. Remember D50 is the aim-point and so far Solux is the closest.
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Photoshop does some amazing things. Not only will it carefully convert image colors into monitor colors on the fly it can also go through a press profile on the way.
This soft-proofing capability is what gives Photoshop the ability to simulate how colors will look if separated using a particular profile OR when sent to a particular device.
This may sound like the same thing but I assure you, it isn't. Let's walk through the soft proofing of two different files to illustrate my point.
First, an RGB file you want to simulate sending to press CMYK. In Photoshop, choose the View: Proof Setup: Custom. For Profile: choose the profile you would use when sending your file to press and for Intent: perceptual or relative colorimetric depending on image content. After clicking OK, Photoshop will soft proof your image to screen. The detailed path your image takes is: working space-> Lab-> press CMYK-> Lab-> monitor RGB. The Lab->CMYK->Lab transformation is what we often call a "round trip" and is responsible for compressing the image gamut and simulating press behavior.
Second, let's soft-proof a CMYK file. Where this CMYK came from doesn't matter too much, we'll soft proof to see how it'll look when sent to press. Open soft proofing the same way as above with View: Proof Setup: Custom. Note, however that this time the "preserve color numbers" checkbox is active. Check it and click OK. You will now see a soft proof simulating how your CMYK file will look when sent to press. The detailed path of the file is CMYK-> Lab-> monitor RGB.
Here's the important part. Had you not checked the "preserve color numbers" checkbox then Photoshop would CONVERT the CMYK file TO your CMYK press profile and then send it to the monitor. Its path would be: working space CMYK-> Lab-> press CMYK-> Lab-> monitor RGB. See the difference? Let's see it again.
PCN on: CMYK-> Lab-> monitor RGB
That extra step is a big difference. In the first case you are asking "show me this CMYK file as if it were sent directly to press". In the second case you are asking "show me this CMYK file when it is converted to the press profile then sent to press". Unless you are specifically and explicitly wanting to reseparate the file, you want the first case, with preserve color numbers checked.
So, to review: Check "preserve color numbers" whenever you get the chance. Come back and reread this text if you get the urge to uncheck it.
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First, what does a RIP do? Originally a RIP was required to rasterize any vector data you wanted to print. Rasterizing is the process of converting lines and curves into dots. All printing uses dots these days so somewhere along the print path the lines and curves in graphics and fonts need to be converted to dots that can actually be printed. Postscript has been a popular language for describing these lines and curves and Postscript RIPs will take complex page descriptions and ready them for dot-based output.
As RIPs evolved more features were added. Now RIPs give greater control over the printer and preprocess incoming files as well. For printer control you can measure density curves and linearize each channel, change ink limiting and so forth. For file preprocessing you can nest images to save time and paper, apply profiles for matching or proofing, manage print queues for multiple users and many other options.
These features are great. They can speed up your workflow, centralize your administration and increase the quality of your work. BUT, they are not required in order to proof.
Proofing, in the color management world, is the act of transforming your colors to your final output profile and then transforming them again to your printer. If you have sufficient control over your printer and you have good profiles, the match between your printer's output and the final destination can be very good.
We build many profiles for inkjet printers that are driven using the manufacturer's RGB-based printer driver. When you control a CMYK printer using RGB you give up the ability to have the profile manipulate the K channel. While this might cause problems in shadows and can make grays challenging, we have great results overall. Coupled with an accurate reference profile, these inkjet profiles can make great proofs. The most important thing in this workflow is the application. Photoshop and other Adobe applications are now smart enough to perform the "proofing transform" that's required for hard proofs. If you are outside of publishing applications then you may not have the ability to insert your reference profile into the print path and so proofing may be out of your grasp.
So a RIP, while a powerful tool that can add many capabilities to your printing system, is not absolutely required for proofing. Try it without a RIP first. All those features come at the price of complexity so if you can work without it you've simplified your life a bit. Gives you more time to figure out that new cell phone, camera, iPod, microwave oven...
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Adobe Gamma is a small utility that has been around a long time and until recently was always installed with Photoshop. It is still installed with the Windows version of Photoshop but has been replaced by Apple's default calibrator under OS 9 and X so Adobe stopped distributing it with Photoshop for Mac. Both calibration utilities are "by eye" calibrator software that require no hardware.
So why bother with a hardware device? A few good reasons: white point, gamma, color and repeatability.
When you calibrate your display with a hardware device, a few important functions occur. First, the device measures the colors of the phosphors (CRT) or filters (LCD) of your display. Then it sets (often with your help) the maximum output for each RGB channel, balancing them to obtain the white point you requested (D50, D65, etc). Finally it "ramps" up in each RGB channel and sets the gamma in your graphics card. This fine-tunes the curves for each channel, ensuring that they have smooth color transitions from 0 to 255, compensating for any non-linearities in your graphics card or display, and makes sure that equal RGB values are gray all the way from black to white.
When you calibrate with a "by eye" system it asks you which monitor you have (to estimate the phosphor / filter colors), allows you to choose a white point (sometimes letting you fudge it by moving a slider) and also sets the requested gamma in the graphics card. Sometimes the system can obtain the phosphor/filter colors directly from your display through its cable. The problem is that each of these are an estimate and the errors introduced at each step can compound to greatly reduce the accuracy of the resulting profile.
Let's break these down:
- White Point. You asked for D65. A hardware calibrator will measure your display, adjust the maximum output of the graphics card, and ensure you get D65. "By eye" calibration will set the graphics card at some preset and then hope you get something close to D65. Your display's native white point will play a huge role in affecting the actual white you see and the software has no idea whether it's in the ball park or not. Not good.
- Phosphor / Filter Colors. A hardware calibrator measures these for use in the resulting profile. "By eye" calibration may obtain the numbers from the display or it may ask you for what type of screen you think it is and then substitute numbers it has from a table. This means the software is guessing. The results will range from "OK" to "poor" and will mean the more saturated colors on your display could show noticeable hue shifts (tomato reds , purple blues, etc).
- Gamma. If you want a gamma of 2.2 a hardware calibrator will give it to you. Software will show you a small graphic that requires moving a slider until two elements match in intensity. This software method is better than nothing but nowhere near what hardware can do. This also plays a role in neutrals...
- Gray Neutrals. A hardware calibrator measures each R=G=B combination from 0 to 255 to ensure that they create neutral gray all the way from black to white AND that the transition is as smooth as possible. Your display, graphics card, cables, system software and other pieces all conspire to make curves bumpy. Measuring carefully at each step helps smooth them out.
- Repeatability. No matter how good a job you do with "by eye" calibration, the next time will probably be noticeably different. If you calibrate regularly (you ARE calibrating regularly right!?), hardware calibration will keep your system stable. "By eye" calibration could introduce more fluctuation into your system than if you had left it alone! scary.
Should "by eye" calibration be avoided at all costs? Not necessarily. Sometimes you are out presenting somewhere and want the overhead system to look good. If you don't have a Beamer then a quick run through of software calibration can help. It always seems to improve things for me. But for a desktop system you want to believe, use a hardware device. The price of such devices has come down to the point where it is affordable and should really be the first dollars you spend on color management.
As always, send me email with questions, rants, raves you may have. I may not have time to answer them all but some of them may find there way into these articles.
Thanks for reading,
Steve Upton
Please see ColorNews Issue #9 for the first 5 myths:
Please see ColorNews Issue #11 for myths 6-10:
Please see ColorNews Issue #13 for myths 11-15:
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FEEDBACK and FAQs
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CHROMiX ColorNews Issue #11 - Color Management Myths 6-10 |
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============================================================= C H R O M i X C O L O R N E W S
Issue #11 =============================================================
** We've taken over ProfileCity to become the largest profiling service, details below.
** It's Back!!!! The FREE Eye-One Display promotion continues through June
** '5 More Color Management Myths', an article written by CHROMiX ==================================================================== Table of Contents =================
1. CHROMiX News ==================================================================== CHROMiX News ================
Since our last ColorNews issue (December 2003) many things have happened at
CHROMiX is 5!
We are excited to announce that we assumed ICS's ProfileCity custom profiling service.
** Steve Upton will be speaking at the following events:
March 10th, 7:00PM. Pixel Printers, Seattle, WA. Update on latest trends in
July 2004. Steve will be speaking at MACWORLD Boston, MA. Seminar times and
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Color & Product News
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Fujifilm introduced ColourKit Profiler Suite 4.0 at PMA Las Vegas, NV.
X-Rite, Inc. announced its Monaco OPTIX(XR) has been awarded Photo
In PC World's round up review, X-Rite's Monaco OPTIX(XR) was compared with
New ProfileMaker 5 software is now packaged in three vertically focused solutions: ProfileMaker Photostudio, Publish and Packaging. All three are profiling and editing compliant with version 4 ICC specifications and are projected to ship by end of March 2004.
Here are the highlights of each:
- ProfileMaker Photostudio includes LCD/CRT monitor calibration/profiling, RGB, CMYK, Hexachrome(r) and CMYK+Red/Blue output device profiling, enhanced Color Picker module, the newly reformulated Digital Camera Module and Digital ColorChecker SC (semi-gloss).
- ProfileMaker Publish includes LCD/CRT monitor calibration/profiling, RGB, CMYK, Hexachrome and CMYK+Red/Blue output device profiling, enhanced Color Picker and Measure Tool modules plus a new Adobe PhotoShop plug-in that supports multicolor separations and soft & hard-copy proofing. There are also new process control functions that enable working with gradation curves, dot gain and optical density measurements. Also includes new and extended gamut mapping capabilities and a new test chart generator with which users can generate custom test charts optimized for individual output devices.
- ProfileMaker Packaging was developed for packaging and textile printing applications. It includes all of the modules and other features included with ProfileMaker 5 Publish plus a new Multicolor module that supports a limitless n-color multi-color profile generation for up to 10 channels. Also included is a new generic output profiling technology that lets users replace inks in existing profiles instead of making new test charts and re-measuring/re-profiling to avoid times and costs of recreation of plates, cylinders etc. for new test charts. Instead, it is possible to take a spectral measurement of a new color and integrate it into an existing profile - a must for the packaging industry where colors change frequently.
Also new from GretagMacbeth is a New DeviceLink Module for ProfileMaker 5 that has a new Preserve Black function as well as Clean Black and Clean Primary options for RGB/CMYK workflows. It can automatically adopt ink coverages and tailor DeviceLink profile generation to specific needs. Inks can also be saved by redefining the separation data without losing the overall characteristics of a device. Projected to also ship by end of March.
Adobe Systems Incorporated announced a new Camera Raw plug-in for Photoshop(R) CS, extending raw file support to 14 additional digital camera models. Available as a free download from Adobe's Web site, the plug-in builds on the raw file functionality integrated in Photoshop CS, adding new support for digital cameras from leading manufacturers such as Fujifilm, Kodak, Leaf, Leica, Nikon, Olympus, Panasonic, Pentax and Sony. It can be downloaded for free by going to the Adobe Web site at
SHOWS & EVENTS
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March 5-8 Professional Photographers of Oregon Convention & Trade Show at the Embassy Suites in Tigard, OR. For more information go to
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ColorFAQs
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Each month, our President Steve Upton will take time to answer questions
As there seems to be no end of strange color management advice offered these days, it seemed like a good idea to dispel a few more myths we've run across recently.
Please see ColorNews Issue #9 for the first 5 myths:
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Not true! although it helps....
Seriously, color management still isn't quite at the "cookbook" stage - where you can just press buttons and it all works - but it is getting close. We regularly sell and install monitor calibrators, profiles and other color management gear in clients who don't really want to know too much about it - and they're happy with the results.
Those who have entered into the world of color management will agree that the water is very deep. There seems to be no limit to how much you can learn and how far you can go in the pursuit of "perfect color".
Rest assured though, you can get into color management and take control of your imaging without breaking either your bank account or your brain!
While this seems to be happening less often as in the past, a recent article in a popular photo magazine article contained this dubious piece of advice.
If you set Photoshop to use your monitor profile as your working space, all new RGB documents will be created using your monitor profile as their gamut definition. This is a bad idea for a handful of reasons:
1. All colors will be limited to the gamut of your monitor. As all ColorThink users know, the gamut of your monitor (and sRGB for that matter) tends to be smaller than that of most output systems. Inkjets, presses and photographic output methods typically contain cyans, greens, yellows and even some reds and magentas that monitors cannot display. Photoshop 5 and later versions effectively disconnected your RGB file from your display, allowing non-displayable colors to pass through Photoshop and be printed. This is a good thing, don't undo it.
2. Each time your re-profile your display you will have a different working space. Color management is enough of a moving target without changing your working space every 2-4 weeks (you are re-profiling every 2-4 weeks right?).
3. Exchanging files with your monitor profile embedded will cause confusion. The reactions from people who receive files with embedded profiles range from "wha?" to "amateur!". As mentioned in past ColorNews newsletters, when you exchange files with other people you should convert to standard color spaces such as Adobe RGB (1998), sRGB and so forth. Refer to ColorNews issue #8
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This falls in the "When in doubt, be very very safe" realm. All rendering in Photoshop 4 was relative colorimetric so any out-of-gamut colors were clipped. One of the benefits of Photoshop 5's inclusion of ICC technology was the availability of the perceptual rendering intent. Almost overnight, anyone who grasped ICC profile use was recommending the perceptual intent for photographic images and relative colorimetric for spot colors. In fact, some applications go as far as calling the perceptual intent the "photo" intent.
I think a little rendering intent background would help here...
When an ICC profile is calculated, the color conversions are "hard wired" into its internal tables. This means that the gamut-shrinking capabilities of the perceptual intent are built without any idea of any actual image content. It is a sort of "generic" conversion that is intended to work for any image.
Trouble is, if you have an image that is entirely in-gamut for your printer and you choose the perceptual intent, your image will be desaturated unnecessarily. The can range from a barely noticeable shift of near-neutrals to a significant dulling of saturated colors.
Configure Photoshop's Proof Setup with your printer profile. Then invoke the gamut warning (shift-command-Y Mac or shift-control-Y Win) prior to converting your file. If you see a bunch of out-of-gamut colors in important areas of your image, choose the perceptual intent when you print. If few colors seem affected, chances are that relative colorimetric (with black point compensation ON) is a better choice for your image.
"Use perceptual for shrinking your gamut in a friendly way, relative colorimetric for color accuracy and absolute colorimetric for proofing. Don't bother with saturation unless your doing business graphics like graphs"
This has been the line about rendering intents that has been passed around a lot. I have to admit that I had been one of the ones passing around until a few years ago when I started to actually test the saturation intent of profiles we were building.
Most profiling software creates the saturation rendering intent in the same manner as the perceptual intent. So the most likely time you will want to use it is if you are shrinking the gamut of your image and you want to retain details in out-of-gamut colors. In our experiments we've found that the saturation intent will map out-of-gamut colors to brighter and cleaner colors rather that more accurate ones. The color shifting performed by the saturation intent will differ between different profiling packages so your results may vary.
At any rate, if you are not satisfied by the saturation in your profile's perceptual rendering intent, give the saturation intent a try. You may be pleasantly surprised by the results.
We build a lot of profiles here at CHROMiX and with the assumption of ProfileCity's profiling business we expect to build a lot more. A big part of building profiles for people is supporting them. It's something we feel differentiates us from the rest.
One question that seems to crop up regularly in our support team is that of the "freshness" of profiles. People call to ask how long their profile will last or to explain a problem and wonder if their profile has gone bad.
Profiles are hermetically sealed, antibacterial, non-fungal, disease resistant, fade-proof, rust-proof, colorfast little wonders. That is (I guess it needs to be said) they do not undergo any change as they sit on your hard drive and will not experience wear and tear even with years of use.
The devices they represent however, are a totally different matter. If your profile worked well one day and then poorly the next, something in the path to (or from) that device has changed. Most problems seem to arise from a change in consumables. Other common problems include updated software or a maintenance issue - like clogged inkjets with a printer.
When your print profile was first built, a certain CMYK/RGB combination produced a certain Lab color. All the profile knows is that relationship and if anything changes the color produced, then the profile is no longer appropriate for the printer.
There are some cases where all the testing of a profile was with a certain image type so the entire capability of the profile/device was never tested. A similar thing can occur when, for example, a CMYK profile is successfully used for proofing and months later, when the profile is used for separations, a problem shows up. In both these cases the flaw was always present in the profile and incomplete testing lead the user to believe it was a good profile when in fact it was not...
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Well, that's another 5 myths. Even as I wrote this article I remembered new ones so keep a lookout for future issue to cover new and interesting color management misunderstandings. As always, feel free to send us some feedback or questions for future ColorNews newsletters.
Steve Upton
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CHROMiX ColorNews Issue #12 - Profiling Overhead Displays |
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============================================================= C H R O M i X C O L O R N E W S
Issue #12 =============================================================
** The transition of ProfileCity into CHROMiX is complete. All ProfileCity.com web requests are directed to a special section on our site and we continue to offer customers the same great profiling packages using the same ICS technologies that ProfileCity customers are accustomed to. Some changes to the service include: all services post-paid - no need to buy a profile to download the kit, CHROMiX industry-leading 100% price guarantee extended to new ProfileCity profiles, expanded profile naming - no longer cryptic numbers, all ProfileCity profiles have longer meaningful names. Please contact us if you have any questions or comments. ** BEAMER WEEK! Buy an Eye-One Photo or Eye-One Publish during the week of April 26 - 30 Only, and get a FREE BEAMER Upgrade and Storage Case. And yes, you can combine the FREE Eye-One Display deal (below) as well. See details below. ** It's still here!!!! The very popular FREE Eye-One Display promotion continues through June 30, 2004. See details below. ** 'Calibration & Profiling of Overhead Display Systems', an article written by CHROMiX President Steve Upton that you'll want to read. ==================================================================== Table of Contents =================
1. CHROMiX News ==================================================================== CHROMiX News ================ Since our last ColorNews issue (December 2003) many things have happened at CHROMiX that are worth mentioning: Our ColorThink software has been awarded the "Best Graphic Design Software" winner from Real Software. Software packages built using their development tools were eligible for the award and were judged on excellence in design, functionality and most complete adoption of advanced technologies. We are honored to awarded this recognition and happy that ColorThink is receiving this recognition. CHROMiX has formally joined the Color Management Group, a consortium of the top Color Management experts in North America. The Color Management Group has associates from coast to coast USA. We are excited to be a part of a larger circle of minds and talent!
CHROMiX's integration of ICS's ProfileCity custom profiling operations has gone much better and faster than expected. CHROMiX ColorValet profiling service is now the largest profiling service in the world!! However, you won't catch us standing on our laurels. We are still extremely obsessed with making the best custom profiles in the world for each and every customer. We look forward to an opportunity to prove this to you! Here's the original news release:
The very popular FREE Eye-One Display promotion from CHROMiX continues and gets better!!
If you're a CHROMiX Partner and have not received your commission check, or if you feel that the check is incorrect, please let us know. We want your feedback so we can evolve this into a world class program for you.
** Steve Upton will be speaking at the following events:
July 15, 2004, 2PM - 3:15PM. Steve will be speaking at MACWORLD Boston, MA.
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Color & Product News
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GretagMacbeth has set the release of ProfileMaker version 5 profiling and color management software to May 15,2004. We at CHROMiX have been beta testing ProfileMaker for GretagMacbeth and are excited about the new features including custom target generation, enhanced multi-color profile and a significant upgrade to the camera profiling module. Expect the release information posted in the next issue of ColorNews.
The makers ColorBlind are looking to re-invigorate the entire product line. Quik Pix, Inc. (QPI), a division of Dalrada Financial Corporation (DRDF), has apparently hired additional applications engineers, software programmers and customer support personnel.
Pantone and ColorVision released ColorPlus, a $119 package targeted at home users that includes a sensor and a wizard-guided software that steps the user through simple monitor calibration. This new calibration package is only available for Windows and does not allow the user to set gamma, white point or offer any PreCal function. While we recommend the 6500K white point and 2.2 gamma it uses as defaults, the omission of the PreCal ability - where you can tune your monitor to get it close to the desired white point - is a significant omission. We are in the process of evaluating this package.ColorVision is focusing it on the home-user market and we suggest that it is not appropriate for professional or photo enthusiast use.
There's a very entertaining article by Eamon Hickey that focuses on the Digital Workflow implemented by Sports Illustrated for Super Bowl XXXVIII at the Rob Galbraith Digital Photography website. Although the color management portion is one small paragraph on page 3, this is a very good and realistic read for Photographers of all walks.
Tech Notes
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CHROMiX ColorNews articles are a useful resource for technical information. In every issue is an article that usually covers a technical topic of merit to users. ColorNews articles are archived and available for your FREE access at
Overheard on the ColorSync mailing list:
If you are having trouble with an Epson 2200/2100 printer under Mac OS X it may be due to the Gimp-Print driver which is the default driver under OS X v10.3. Some users are funding success in trouble-shooting the problem by removing the Gimp_print driver and installing the drivers that come on the CD included with the printer.
Several Mac OS X users have asked us how to understand the impact of the GIMP print driver in their system. One of the best places for this information is the Gimp-Print website. You will find the ESP Ghostscript version 7.05.6, the Gimp-Print un-installer and many technical and support links and pages available:
Also:
Many people have asked us what reference material we recommend. As a desk side technical reference, 'Real World Color Management' from Bruce Fraser and Chris Murphy is the 'go to' standard in the industry (about $39).
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SHOWS & EVENTS
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May 6 - 19, 2004 DRUPA, Duesseldorf, Germany, is the largest Print show in the world. DRUPA is undeniably considered the mecca for anything print related.
May 10, 2004, The Professional Workflow Digital Workshops with Will Crockett have been a great value for all attendees. The best value is that these events have been FREE. The last stop and end of the tour is in Chicago on May 10, 2004.
May 27, Portland, OR. Pacific Northwest Color Management Users Group, is excited and proud to present Barry Haynes, author of numerous articles and the highly acclaimed Photoshop Artistry series. Barry will show techniques including effective work environment organization, Color correction, masking, use of color spaces, and some new insights on monitor and printer calibration! This lecture event is 5/27/04 at 6:00PM at The Oregonian. For more information and event registration go to:
June 17 - 19, 2004 Guttenberg Festival. Long Beach Convention Center, CA. Now in its 32nd year, this annual Southern California event is the hot spot for graphic design, digital prepress, printing, publishing converting and digital equipment professionals. Over 200 exhibitors will be on-hand to display products on over 60,000 net sq feet.
July 12 - 15, MacWorld, Boston, MA. Everything for the Mac devoted. East Coast style. Steve Upton will be speaking.
July 15 - 17, InDesign 2004, Boston, MA. Get personal with the world's premier experts, authors, trainers, and third party developers for 3 days of unparalleled Adobe InDesign training, tips, techniques and networking.
October 10 - 13, 2004 GRAPH EXPO and CONVERTING EXPO at McCormick Place
October 24 28, 2004, XPLOR 2004, 25th Global Electronic Document Systems Conference & Exhibition at Dallas Convention Center, Dallas, TX.
January 10 - 14, MacWorld San Francisco, CA. Everything for the Mac devoted. West Coast style.
March 17-19, 2005 Graphic Arts 2005. Charlotte Convention Center, NC. This recent trade show and conference brought in thousands of industry professionals from the Southern USA. View the many highlights of the 2003 show edition and sign up to be reminded of the next show in Charlotte, NC.
September 9-15, 2005 PRINT '05 at McCormick Place Complex, Chicago, IL Because of its mammoth size and international presence, PRINT occurs only every four years and will take the place of GRAPH EXPO and CONVERTING EXPO in 2005.
ColorFAQs
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Each month, our President Steve Upton will take time to answer questions we receive on a regular basis. If you have specific questions or comments, please see below for how to make submissions.
Yes in fact, it can. With the right equipment and software you can calibrate and profile your overhead display system. It makes a considerable difference as well. Neutrals look neutral, correct saturation stops your images from looking washed out or artificially punchy. The hues of important colors like logos also look correct. This is especially important if your presentation includes your client's logo and other corporate colors.
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In North America a "beamer" is what yuppies call their BMW. In Europe a "beamer" is the common nickname for an overhead projector system. In Color Management a Beamer is an overhead calibration system from GretagMacbeth. As far as we have been able to determine, it is the only overhead display calibration and profiling solution offered on the market today.
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Well, it is similar to calibrating your monitor with a little more setup. Basically you connect your computer to the overhead display projector and set it up like normal. Make sure you have the contrast and brightness set the way you like and the image is clear and stable. Then you attach the Eye-One spectrophotometer to a small stand that allows you to aim it at your overhead system's screen. A small white dot appears on the screen allowing you to fine-tune the spectro's positioning. Then the calibration and profiling proceeds in a similar (if somewhat larger) fashion to monitor calibration.
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Pretty much, yes. Just like your monitor, the curves in your computer's graphic card are adjusted until the screen shows the desired white point and gamma. Then an additional series of colors is measured to build a profile characterizing the system. The calibration curves are embedded into the profile and it is saved and set as your system's profile. All this is just like a conventional display profile.
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As mentioned above, it neutralizes neutrals, calibrates white point and gamma and, when an application uses the profile, helps display correct hues & saturation.
From a bigger-picture perspective, it helps you make your point. It makes your image more professional and your competitors wonder what they're missing.
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Not typically. Just like a conventional monitor, calibration and profiling of a display system involves the display AND the graphics card in the CPU. The combination of the two is what's calibrated. The overhead display system will behave differently connected to a different CPU and so each combination needs to be calibrated separately. This is one of the first questions we typically hear. If the CPUs are very similar (like the same model PowerBook, for instance) then you may get away with it. In most cases however, it's time to re-calibrate.
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If you have a monitor connected to your computer in addition to the overhead display then you may want each of them calibrated.
You can calibrate & profile each if:
- your monitor and the overhead display are connected to different graphics cards (for Mac or Windows) or a two-headed graphics card (Mac).
You can NOT calibrate & profile each if:
- your CPU is connected to the overhead display with the same cable as it is connected to a monitor.
If you can't, calibrate the overhead and live with the other display looking a bit "off" while you present. Select your regular display profile when your presentation's over to return to normal (Windows systems will require a reboot to load the correct calibration tables).
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DVD player software is not color managed. That doesn't mean that calibration won't improve your display however. Setting a desirable white point, fixing the gamma curves of each RGB channel to 2.2 and nailing down your grays will all help raise the quality of your DVD playback.
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Photoshop and other applications that can use a display profile will go the extra step of ensuring that color hue and saturation will be as correct as display gamut will allow.
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That's a good question. If the presentation package is color aware like Safari, then you have no worries. It will color manage your images for great display quality. For PowerPoint users on Windows, GretagMacbeth includes a plug-in that allows the color management of images within your presentations.
Thanks for reading,
Steve Upton
In a visit to CHROMiX.com or profilecentral.com, you opted to receive this newsletter. You may have also heard Steve Upton speak and requested more information. If you have received this message in error, we apologize. We value our relationship with you and do not want to spam you. See below for details on how to provide feedback, how to unsubscribe, or how to become a sponsor.
FEEDBACK and FAQs
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Getty Images Test Image |
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The Getty Test image is no longer available. See other test images at www.colorwiki.com: http://www.colorwiki.com/wiki/Test_Images
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CHROMiX Announces ColorNews RSS feed |
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June 2, 2005: Seattle WA: CHROMiX, Inc. today announced the launch of the ColorNews RSS Feed service. New service allows rapid updates of events and announcements pretaining to the Color Management and associated industries. | |||||||
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CHROMiX ColorNews Issue #15 - To RIP or not to RIP |
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Welcome to ColorNews, a periodic update on things related to Color Management. We are striving for a regular consistent newsletter of high value to our customers. Please let us know what your interests are so we can address these concerns in our coming issues.
============================================================= C H R O M i X C O L O R N E W S
Issue #15 =============================================================
** There are several new Monitor calibration devices released this month: the Eye-One Display 2 from GretagMacbeth, ColorEyes Display from Integrated Color Corp., and the Spyder2 from ColorVision. Details on all below. ** Monaco's $50 Rebate for Optix XR and Optix XR Pro has been extended until the end of the year! See ad below. ** CHROMiX is extending our new "Buy it Back" trade-in program. CHROMiX will buy your old competitive monitor calibration device when purchasing Eye-One profiling solutions. We'll pay you $80 when you buy an Eye-One Display and $200 when you buy an Eye-One Photo, Publish or Beamer. Contact Sales for more information. See Ad below. ** 'To RIP or not to RIP', an article written by CHROMiX President Steve Upton ==================================================================== Table of Contents =================
1. CHROMiX News
CHROMiX News ================ Since our last ColorNews Issue #14 (August 17, 2004) many things have happened at CHROMiX that are worth mentioning: CHROMiX ColorThink Pro version was extensively mentioned and used (for imagery) in the newest version of Real World Color Management. CHROMiX was at Graph Expo in Chicago Oct. 10 - 12. We participated with other members of the Color Management Group. Rick Hatmaker was there giving many demos of ColorThink software (2.1), discussing ColorValet/Profile City profiling services and discussing color management with show attendees. A summary of the noteworthy items at Graph Expo is listed below in the special Graph Expo Summary section (with a color management perspective of course). CHROMiX will be at Photo Plus in New York Oct. 21 - 23. We'll be in booth #976 with Integrated Color Corp., ImageLink and See File Asset Management. We will be showing off ColorThink and discussing color management for photographers. Come by the booth and receive a 10% coupon off our CHROMiX branded products ColorThink and ColorValet! Quarterly Commission checks went out to Partner Program members this month, and we are increasingly amazed by these amounts! We are very much appreciative your referral business!! Please let us know if you did not get yours.
If you think you could benefit from a little extra cash every quarter, then check out the CHROMiX Partner Program. It's very easy. And you get paid by just referring others to a reliable, knowledgeable color management resource called CHROMiX. Simply go to
==================================================================== Color, Product & Industry News ====================
GretagMacbeth has announced the NEW Eye-One Display 2, an evolved version of the top selling Eye-One Display monitor calibration and profiling product. The Eye-One Display 2 touts 'one button color management' for your CRT or LCD monitor and much greater control than it's predecessor.
GretagMacbeth announced the Eye-One iCare Program. iCare is a premium extended warranty and accuracy verification program for Eye-One Pro customers! The cost is $395 List and iCare can be purchased anytime within the standard warranty period.
Integrated Color Corporation announced COLOREYES DISPLAY, for use with all monitors, CRTs and LCDs. ColorEyes Display will be sold with X-RITE's DTP-94 monitor calibrator because of its precision and repeatability. ColorEyes Display is based directly on the core technology behind "Remote Director" developed by Integrated Color Solutions (ICS). There's a new FREE 2-page downloadable 'Photoshop Printing Tipsheet' from Color Remedies (aka Chris Murphy) that is very good. You can find it at: here
Manufacturers of profiling software have been, and will continue to release versions that produce profiles that conform to v4 of the ICC specification. Other software manufacturers are developing and releasing applications that will utilize ICC v4 profiles. For a list of these vendors, follow this ICC link and download the pdf:
The 'Professional Workflow 2 Digital Workshop' from ShootSmarter.com is starting a new FREE tour across the U.S.A. starting in Seattle on January 10, 2005. Check this schedule and see if it's coming to a city near you!
Adobe has updated and released Camera Raw version 2.3 (RAW file format plug-in for Photoshop CS) for Windows and Mac. Version 2.3 adds the Canon Powershot S60, Epson R-D1, Fujifilm FinePix S20 Pro and Nikon Coolpix 5400 to the growing list of RAW files the software can convert. In addition, Camera Raw plug-in also supports Adobe's newly-announced Digital Negative (DNG) format here
ColorVision has released the new Spyder2 colorimeter with new & improved pro-level monitor calibration software. The Spyder2 features: Precise calibration of CRT, LCD, and notebook displays (Mac and Windows), Wizard software with easy-to-follow instructions (site license), Gray balance and tonal response, Accurate flesh tones, Multiple monitor calibration and matching, 2 Year Spyder2 Warranty and free technical support. For more details go to: Creo Leaf and GretagMacbeth have entered into a cooperative agreement to provide Leaf customers the ability to customize ICC color profiles to fit different lighting conditions based on the shooting environment. The solution integrates GretagMacbeth profile creation and editing products into the Creo Leaf Capture 10 application. The user will be able to create ICC profiles that takes into account unique and specific lighting for different shoots.
Good Economic news! Printing Shipments were Up for the Third Straight Month! According to Dr. Joe Webb, editor at What They Think.com, "Printing shipments for August 2004 were up $21 million compared to August 2003. This is the third straight month of increase, unadjusted for inflation. We are now at -0.5% for the first eight months of 2004 compared to 2003. This is, of course, good news, and combined with the ==================================================================== SHOWS & EVENTS ================ *! October 21-23, 2004 PhotoPlus Expo at Jacob Javits Convention Center New York, NY. This is the East Coast's largest and most comprehensive expo in the photographic and imaging industries. There will be over 200 exhibitors, new & live product demonstrations, hot products sold direct, top industry seminar and keynote speakers & presenters. *! CHROMiX will be at PhotoPlus Expo in booth #976 with Integrated Color Corp., ImageLink and See File Asset Management. . We will be showing off ColorThink and discussing color management for photographers. Come by the booth, say hello and receive a 10% coupon off our CHROMiX branded products ColorThink and Colorvalet! October 24 28, 2004, XPLOR 2004, 25th Global Electronic Document Systems Conference & Exhibition at Dallas Convention Center, Dallas, TX. here
*! December 5-7, 2004, the GATF 6th Annual Color Management Conference has been announced and will be held at the Hilton Pointe Mountain Tapatio Cliffs Resort. Steve Upton has been asked to serve on the board of directors this year and will be speaking in several sessions and Labs. More details to come.
January 10 - 14, MacWorld San Francisco, CA. Everything for the Mac devoted. West Coast style.
March 17-19, 2005 Graphic Arts 2005. Charlotte Convention Center, NC. This recent trade show and conference brought in thousands of industry professionals from the Southern USA. View the many highlights of the 2003 show edition and sign up to be reminded of the next show in Charlotte, NC.
September 9-15, 2005 PRINT '05 at McCormick Place Complex, Chicago, IL Because of its mammoth size and international presence, PRINT occurs only every four years and will take the place of GRAPH EXPO and CONVERTING EXPO in 2005. ==================================================================== SPECIAL: GRAPH EXPO 2004 NOTEWORTHY ITEMS ================
X-Rite launched a new campaign and strategy called 'Streamlined Color Management'. This appears to be X-Rite's new global strategy for the graphics arts market, with an emphasis on simplicity, usability, and affordability. There are three keywords to this new strategy: CREATE, PREPARE and EXECUTE. JUST Normlicht, Inc. showed the new 'proofStation'. JUST is setting new standards in design, functionality and innovative lighting technology with improved light distribution, luminance levels and unmatched color rendering qualities. CHROMiX was so impressed that we decided to carry this fine product line! ICS (Integrated Color Solutions) showcased Remote Director, the first SWOP Certified monitor-based contract proofing system that applies advanced color management to verify the accuracy of every monitor and every proof. Running on commercially available hardware, Remote Director software allows multiple reviewers in dispersed locations to view, collaborate and comment on color as well as content and build a digital record of the proofing process from start to finish including legal sign-off. GretagMacbeth showed their new products including the new Eye-One Display 2 and the DensiEye 700. They were also showing show attendees new aspects of Eye-One Shares ability to match and compare spot colors. GretagMacbeth also discussed and promoted their new Brand Program to leverage service products to customers. The Color Management Group (of which CHROMiX is a proud member) promoted it's members and demonstrated it's collective and individual products and services that help control color throughout the workflow. Left Dakota released and demonstrated it's new UltraLinks software, creating ICC links which convert RGB to CMYK while maximizing the color gamut; and Link-o-Lator products, helping the high-end color management user create the most accurate digital color proofs. Jim Rich of Rich & Associates promoted and discussed The RIP Report: Using and Choosing ICC-based RIPs that Drive Inkjet Printers. This raster image processor (RIP) primer offers practical information about ICC-based RIPs, calibration, color management, and buying advice about ICC-based RIPs that drive inkjet printers. Quark released QuarkXPress v6.1 that will feature a more intuitive, versatile interface. Quark also relaxed their Single-User Licensing Policy. Under the new policy, QuarkXPress 6 users can install and activate their software on a second computer at no additional charge.
ColorFAQ - To RIP or not to RIP?
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With the proliferation of inexpensive inkjet printers it seems everyone can now afford one and most professional imaging people have one (or more). Most inkjets on the market - even the wide-format variety - are available without a RIP and are accessed through the manufacturer's print driver. We receive a constant stream of questions about RIPs: what they do, how they work, are they required. It seems high time to put together an overview of RIPs' basic functions and uses. Strictly speaking, a RIP is a Raster Image Processor. Not since the days of pen plotters have lines and curves in software actually been drawn as lines and curves on paper. All major printing technologies create pictures, linework and text using a grid of dots sometimes called a Raster. To create this grid of dots, software is required to convert line work (curves, text, and so forth) and images to a printable matrix of pixels and then screen them using a complicated pattern of cyan, yellow, magenta and black ink dots. With the advent of Adobe's Postscript page description language our software had the ability to create entire pages of text, artwork and images using raster and vector commands that could then be printed on any printer that could interpret Postscript. Postscript is not an open language but Adobe licensed it to many printer manufacturers so we can use the same printing language to print to our laser or inkjet printer that we use to print a final job on press. The RIP software engine that interprets the Postscript often resides in printers themselves but can also run on a purpose-built computer directly connected to the printer or (as is becoming more common) on a desktop or server computer running Windows or Mac operating systems. Like most things in the computing world, RIPs have evolved mostly by adding feature after feature. Many of these features have nothing to do with rasterizing Postscript but make good sense to have on the same computer. RIPs now share printers across a network to multiple users, allow printing queue management for prioritizing of print jobs, nest jobs to save paper, and so forth. A number of features that DO control or affect color are: linearization, ink limiting, screening & dot simulation, direct channel control and color management. Let's handle them one at a time. Linearization - straightening out the behavior of each channel makes a printer much more palatable to print profiling. RIPs have traditionally linearized based on density measurements but this is not necessarily linear as far as our eyes are concerned. Some RIPs are starting to allow linearization based on L* (the L in Lab) or Chroma (the C in LCH, a cousin of Lab). This type of linearization makes profiling much simpler and tends to increase accuracy as well. For printers that include light cyan and magenta inks, most RIPs allow control over light and dark ink blending to smooth the transition between inks. Ink Limiting - inkjet technology is all about the relationship between ink and paper. RIPs can allow limiting of the ink in each channel as well as the total ink limit allowed on paper (good RIPs allow both). There are two strategies to ink limiting each channel. One is to set the inking limit to the point just before the ink puddles on the paper. This allows for the maximum gamut possible from the printer. Unfortunately, when laid down heavily, inkjet inks can behave rather strangely by changing their hue. This causes "hooks" at the end of each channel (easily seen when graphed) and profiling software can struggle to capture this behavior properly, causing inaccuracies in saturated colors. Accordingly the second strategy is to limit the ink to a point just before the sharpest part of the hook occurs. This can be an effective trade-off between gamut and inaccuracy and is popular for proofing systems where the target gamut is defined by the proofing / reference profile. Setting the ink limit to be just high enough to contain the reference gamut is sometimes the only way to get the accuracy proofing systems require. Screening and dot simulation - Once vector and line work has been rasterized into pixels it needs to be screened into dot patterns. Most inkjet screening is stochastic / chaotic or something similar. Randomizing the dot patterns can create beautifully smooth tones but they are certainly different from the patterns typically seen on press. Some RIPs will simulate the dot patterns on press but it is tough to do this effectively as each dot needs to be color managed to simulate press inks and then they require blending as is seen on press. While this type of proof can illustrate dot pattern problems that may occur on press (like moire) its limitations are slowing its acceptance and most proofing is accomplished with non half-tone screening. Direct Channel Control - Controlling a 4 channel CMYK printer using 3 channel RGB numbers means giving up on influencing the black channel. You may be able to control black better than the "canned" separation that occurs in a printer driver. Controlling a (true) 6 channel printer using 3 channel RGB numbers is even worse. On the other hand, RGB profiling solutions tend to cost less than CMYK and considerably less than 6-channel profilers. Like everything in life, greater control tends to mean greater complexity and cost. If you want it however, it's typically there for a price. Color Management - the CMYK to CMYK color transformation that is required for correct proofing can be accomplished in desktop applications but it is much simpler to perform it in-RIP. When the proofing transform is moved to the RIP, any application can print CMYK and create good proofs. All applications (and all users) will create the same quality proof and page elements such as EPS graphics - which are typically un-manageable in applications - will proof correctly in-RIP. Another in-RIP capability which is often overlooked is the substitution of vector colors. Important client logo colors can be carefully formulated when tuning the RIP so at print time they are pulled from the Postscript print stream or PDF and substituted with the tuned color for your RIP. So if a RIP is so powerful then why would we ever print without one? Well, with the power comes the price of complexity. In the past few years RIP interfaces and installation procedures have improved significantly but they still require more time and knowledge than printing from drivers. Also, drivers are included with the printer but RIPs can cost significantly more. They typically run on a separate computer so that also needs to be figured into the price. What are the limitations with drivers? The most important limitations are the inability to linearize and the lack of direct channel control. If you use third-party papers or inks in your inkjet and find that no matter what you do it clobbers your shadow detail then linearization may be just the thing you need. If you can't keep neutrals neutral, find saturated colors muddy or struggle with a lack of dark saturated colors then direct channel control and its ability for you to specify black generation may help you as well. It's fair to say that a RIP will almost always give you better results than simply controlling your printer with standard drivers. It's certainly correct to say that a RIP will complicate your life and add to the cost of your printing system. If any of the above points rings true for you then it might be time to consider a RIP. If not, consider yourself lucky and forge ahead with your driver. If you are really not sure then try a good custom profile using your driver. It's a comparatively cheap experiment to see if the driver will do the job before heading down the RIP road. Thanks for reading,
Steve Upton
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= In a visit to CHROMiX.com or profilecentral.com, you opted to receive this newsletter. You may have also heard Steve Upton speak and requested more information. If you have received this message in error, we apologize. We value our relationship with you and do not want to spam you. See below for details on how to provide feedback, how to unsubscribe, or how to become a sponsor.
1ea used Monaco Optix XR (New $269) $239 1ea X-Rite DTP-22 Digital Swatchbook (serial) $699
FEEDBACK and FAQs
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CHROMiX ColorNews Issue #16 - Color Management Myths 21-25 |
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Welcome to ColorNews, a periodic update on things related to Color Management. We are striving for a regular consistent newsletter of high value to our customers. Please let us know what your interests are so we can address these concerns in our coming issues.
============================================================= C H R O M i X C O L O R N E W S
Issue #16 =============================================================
There are many diverse things going on this month, and we would like to draw particular attention to these items: ** This month we announce the CHROMiX ColorForums. ** For those of you who were waiting for a price reduction of ProfileMaker v5 UPGRADE, GretagMacbeth has a 30% off sale until December 31st. See ad below for details. ** GretagMacbeth has just announced a completely NEW reconfiguration of the Eye-One Pro line-up. CHROMiX has made sense of it with a matrix we think you will find useful. See details below. ** The X-Rite Pulse ColorElite is now shipping!!! See details below. ** The X-Rite DTP-70 and DTP-45 and Monaco Profiler 4.7 are also shipping! See details below. ** Color Myths Continue, an article written by CHROMiX President Steve Upton ==================================================================== Table of Contents =================
1. CHROMiX News
CHROMiX News ================ Since our last ColorNews Issue #15 (October 20th, 2004) many things have happened at CHROMiX that are worth mentioning:
CHROMiX ColorForums : This month we are very excited to announce the CHROMiX ColorForums. We've been working for months finding the right tools, configuring our server systems and setting things up just right. ColorForums.com is the first full-featured online forum dedicated to color management tools, techniques and support. Not only is there a clear web-based interface to all forum topic areas but it is backed up with a comprehensive email system. You can read and post messages via the web or email, so those of you who don't always have time to surf the web can have the color management community come to you. So pay the ColorForums a visit when you have questions or just want to discuss color management. CHROMiX is proud to announce the appointment of Anne Taylor as Director of Training and Consulting Services. Anne is a well-known prepress and printing veteran and was recently with Corbis setting worldwide imaging standards. Readers of previous ColorNews issues will recall that we've been working with Anne for a while now. Things have been going so well we decided we could really benefit by tapping her leadership skills. Expect to see more consulting and training offerings from us in the future.
Steve Upton is the featured speaker in a free QuickTime-based seminar sponsored by Apple and GretagMacbeth. CHROMiX ColorThink Pro is extensively mentioned and used (for imagery) in Real World Color Management Edition 2. Thanks, Bruce and Chris, for the inclusion! CHROMiX ColorThink Pro is almost ready! Stay tuned, details to come very soon!!! CHROMiX was at the recent GATF conference in Phoenix. Steve Upton and Anne Taylor gave presentations, sat on panels, helped plan events, and were generally seen whichever way you looked. Thanks to everyone who took the time to speak with Anne and Steve! We want to thank our many CHROMiX Partner Program partners, who have helped make 2004 a great success. We would appreciate any comments as to how we might make 2005 even better. Please email your ideas to Rick Hatmaker at hatmaker(at)chromix.com or call (866) CHROMiX ext. 7. We look forward to a very successful New Year with all of our Partners. Happy Holidays!
Did you know that CHROMiX ColorValet is the world's largest and most comprehensive PROFILING service? It's true! ==================================================================== Color, Product & Industry News ====================
GretagMacbeth has almost completely re-configured the Eye-One line. Eye-One Design and Eye-One Proof are completely new bundles. Eye-One XT replaces Eye-One Publish (which is gone). And Eye-One Photo has the same name but has added more components. The Camera and Editor modules will ship separately when released in early 2005. Shipping should be soon, so stay tuned. Also, CHROMiX will continue to include a FREE Eye-One Display with each Eye-One Bundle. The Eye-One line is a little confusing, so CHROMiX has provided a simple matrix to help you understand the differences in the packages. You can find it here: here or give CHROMiX ColorGear Sales a call to discuss which one is right for you at 866-CHROMiX x1 or email sales(at)chromix.com GretagMacbeth released Eye-One Match 3.0 for Mac and Windows, an update to the application supplied with its Eye-One Display, Eye-One Design, Photo, Proof, XT and other Eye-One hardware packages. The improvements are significant, and version 2 owners can upgrade for free. For more information, go to: here
GretagMacbeth has fully implemented it's Eye-One iCare Program. iCare is a premium extended warranty and accuracy verification program for Eye-One Pro customers! The cost is $395 List and iCare can be purchased anytime within the standard warranty period.
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Here is a link to view the different configurations and CHROMiX ColorGear prices: And, if you've purchased Monaco EZ-Color, X-Rite is offering a $199 Trade-In rebate to Pulse Color Elite System for your Ez-Color. For more information call CHROMiX sales at 866-CHROMiX extension 1.
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Adobe announced an effort to standardize raw digital camera formats and will offer DNG spec as the standard format for storing raw files from multiple vendors' cameras. ColorNews had a previous mention of this item, but felt it was worth a second mention.
TECH NOTES
We found a great article worth your visit if you've ever wondered when to use JPEG, TIFF or RAW files generated from your digital camera: 'File Formats Made Easy', by JoAnne Carter One of the biggest challenges for Pro photographers using digital workflows is time they spent (or wasted) managing their digital photos. It can require many applications and resources to accomplish a task that is increasingly complex.
Extensis has an application called Portfolio v7, that helps photographers to streamline their workflow and automate many of the tasks that cut into their time behind the camera. Here is a downloadable PDF tech brief about it that's worth a read if this is your problem too: Phase One also has a product called Capture One (or C1 for short) for photographers that addresses workflow and automation. There are Windows and Mac OS X versions 3.6 of C1 PRO, SE, LE 3.6. These applications are great image and workflow additions for digital SLR and compact cameras. Download a Mac demo at here ==================================================================== SHOWS & EVENTS ================
January 10 - 14, MacWorld San Francisco, CA. Everything for the Mac devoted. West Coast style. February 20 - 23, PMA 2005 and DIMA 2005 Orlando, FL at the Orange County Convention Center in Orlando, Florida. For more information: here here March 17-19, 2005 Graphic Arts 2005. Charlotte Convention Center, NC. This recent trade show and conference brings in thousands of industry professionals from the Southern USA. View many highlights of the 2003 show and sign up to be reminded of the next show in Charlotte, NC. here
May 23-26, 2005 Seybold New York. here
September 9-15, 2005 PRINT '05 at McCormick Place Complex, Chicago, IL Because of its mammoth size and international presence, PRINT occurs only once every four years and will take the place of GRAPH EXPO and CONVERTING EXPO in 2005. ============================================================= ColorFAQ - Color Myths Continue
============================================================= As in previous ColorNews newsletters, there never seems to be an end to the myths and confusions we run across. This month I'll address 5 more.
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= First, a bit about non-colorimetric rendering intents and LUTs. Most monitor and RGB working spaces are made using simple Matrix profiles. Matrix profiles contain color measurements for the RGB channels, curves for each RGB channel and a white point tag. They are small, easy to store and totally depend on the device in question behaving very predictably. In the case of CRT monitors and working spaces, this is no problem. However, when these matrix profiles are used in color conversions, the CMM has little choice of what to do with out-of-gamut colors. There are no instructions in a matrix profile regarding how to treat them. CMMs like the Adobe ACE CMM in Photoshop and other Adobe applications will simply "clip" out of gamut colors to the gamut of the destination. This is the relative colorimetric intent. The perceptual and saturation intents require more detailed instructions on how to treat out-of-gamut (and in-gamut) colors and these instructions are stored in 3D lookup tables (LUTs). So, matrix profiles are simple but can only do colorimetric conversions and LUT profiles can contain the more complicated instructions required by perceptual and saturation rendering. See the problem yet? Another point that needs to be made is that under version 2.x of the ICC spec (not the current spec but the one in wide use today) only one rendering intent is required in input profiles. What this means is that scanner and camera profiles are only required to contain one rendering intent's lookup table and that is the colorimetric one. They may contain additional tables but as they are not required, they are often not included. Getting the picture? No? In plain English this is what it means: - when converting from workingspace to working space (say, Adobe RGB to sRGB), the ONLY rendering intent available is colorimetric. Photoshop allows you to select perceptual and saturation but they make NO difference (try it sometime). Photoshop should gray out intents that don't exist in the profiles.. but that's just my opinion.... - when converting from a scanner or camera profile to a working space the ONLY rendering intent available (in many cases) is relative colorimetric. Again, Photoshop will let you think you have others available but they are not contained in the profiles and choosing them will still give you relative colorimetric. - as a result of these missing intents, you run the risk of clipping out-of-gamut colors AND because many of them are outside of your monitor's gamut you won't notice the problem until you go to print. Joseph Holmes, a well-known and respected photographer and digital imaging fellow decided years ago that this was not what he wanted and he devised a strategy to get around the problem. His idea was to convert from an input profile to a large working space (and he invented his own, Ektaspace) and then archive the image in this form. When he was ready to go to print he would let the (actually existing) perceptual intent in the print profile shrink the gamut of the file in a pleasing way. This way he would bypass the potentially destructive scanner->smaller workingspace or workingspace->workingspace conversions. (he actually went The ICC v4 specification allows for more intents in input profiles but there is no guarantee they will contain perceptual or saturation tables. Over the longer term though we should expect to see these tables in input profiles and we'll have a safer conversion path. Matrix to matrix conversions, however, will always have this problem so be careful. Select your destination workingspace profile in "Proof Setup" and turn on gamut warning in Photoshop to see which colors in your image run the risk of getting clipped. Then either de-saturate colors by hand or leave your image in the larger working space and let the print profile shrink the gamut when required.
The Lab color space as we know it today was created in 1976. The a and b axes are often described by people as the Red and Green axes but this is incorrect. (or at least unclear) Try this test in Photoshop
- open Photoshop
- now enter the Lab color 100,127,0 - this is the most positive "a" value Sometimes when people write or speak about the Lab color space they describe the "a" axis as the red/green axis. As you can see by the above illustration it is better described as the magenta-ish / cyan-ish axis. These axes were chosen for their positioning relative to human perception NOT to make it easier for writers and speakers to describe them. It's easier to say "red/green" than "magenta-ish/cyan-ish" so many people do it. It's no big deal just don't panic when you discover that they're not actually red and green.
This one's from a conversation I had with color management icon Don Hutcheson the other day. There are two methods for setting up the CMYK working space and CMYK conversions in Photoshop and unfortunately Adobe has not made the distinction very clear so there's room for confusion. First, the legacy CMYK system that has been around for many many versions is pre-ICC and is available when you choose "Custom CMYK..." in the CMYK popup of the Color Settings dialog. These CMYK setup options allow you to select ink color values, black generation, dot gain and other parameters. Once selected, Photoshop creates a simplified ICC profile that does not contain a paper white value and also only contains the colorimetric rendering intent. Any other profile selected is a true ICC profile that is used by the Adobe ACE CMM to perform color transformations. What's the difference? Well, the most important thing is that these are very different methods of setting up CMYK conversions and the older engine, while it has lots of options, produces conversions that are fairly crude and not up to today's standards. Another point is that the settings you see in the Custom CMYK setup area have NOTHING to do with the current or previous ICC profile. It's easy to get drawn into thinking that you can select a modern profile and then alter the profile's settings in the custom area. This is not the case however. We urge you to use modern ICC profiles for your CMYK setup. if you feel you want to change the separation settings (which is understandable) then generate your own ICC profiles (in a profiling application) using your desired settings and then select them in Photoshop. Photoshop is not a profile editor and the only profiles it can generate are based on old technology and not enough color data to give quality results.
When creating a new print profile, often the first task is to print a profiling target from Photoshop. Whether you are creating an RGB or CMYK print profile the overall technique is the same. Open the target image file without performing any conversion. Then print the file without performing any conversion. Get the idea? no conversion. Some people are concerned about their choice of workingspace at the time of target printing. But, if you follow the path of no conversions then the workingspace is irrelevant. The only thing it will affect is the appearance of the target on screen. (for information regarding how confusing this can be, see Myth #11 in ColorNews Issue #13 ). Otherwise it has no bearing on the profile you build. There is one case where it may make a difference. ColorVision's scanner-based profiling software makes certain assumptions about outgoing colors when it builds scanner-based print profiles. We don't recommend this method of print profiling as it doesn't measure up to professional quality and it also creates a profile that is dependent on the source color space which is... well.. strange at best, annoying, limiting and confusing at worst.
This one couldn't be further from the truth. But, again, I should start with a little background. When you do a color conversion in Photoshop or other applications, the two profiles in question (say, US Sheetfed Coated and your inkjet profile) are joined together in RAM to form a single transformation. So, while the conversion theoretically goes from CMYK to Lab through the Sheetfed profile and then Lab to CMYK through your inkjet profile, in actuality the two profiles are joined in RAM and the conversion takes place as a single CMYK to CMYK transformation. This is pretty much transparent to you as a user but it does make the conversion faster and may also increase precision. A device link profile is what you'd get if you were to save this combined profile to disk. It permanently links the profiles together using the selected rendering intent. The advantages of this are numerous: - The CMM that was used to create the transformation contributes to the quality of the resulting device link profile. So you can use a good CMM on your desktop computer to create the link and then bypass the idiosyncrasies of the CMM on your RIP, for example. - A normal device link does simply encapsulate a typical ICC color transformation including the tendency to reseparate K-only image elements into CMYK image elements. If this is undesirable (which it often is for re-separating CMYK files for alternate press conditions) then some software can filter the device link after it is created so that K-only color remains K-only after conversion. It will usually be tone corrected for the new profile but it will remain "clean". This is often called "preserve black" or "clean black". - The same "clean" behavior can be applied to the other color channels. As each channel increases to 100% the other inks are minimized, maximizing the purity of the colors. - An emerging technique is to use device link profiles to automate prepress-style edits. Curve bumps, ink limiting and other techniques can be captured in a device link profile and applied en-masse to large numbers of files in a color server or RIP. This can be a very powerful way of applying traditional channel-style edits in an ICC compliant workflow. So, while device links are not widely supported (they are still not usable in Photoshop), they are powerful and can solve challenging color and production problems when needed. Keep an eye on technology that makes use of device link profiles. We have only seen the beginning of what they can do. Thanks for reading, good luck in the new year.
Steve Upton
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FEEDBACK and FAQs
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CHROMiX ColorNews Issue #17 - Delta-E: The Color Difference |
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Welcome to ColorNews, a periodic update on things related to Color Management. We are striving for a regular consistent newsletter of high value to our customers. Please let us know what your interests are so we can address these concerns in our coming issues. ============================================================= C H R O M i X C O L O R N E W S
Issue #17 ============================================================= Quick Notes of Interest: ** CHROMiX is announcing the new Price Guarantee program. See details below. ** The new CHROMiX ColorForums are proving to be a useful support service according to polled users. If you have a technical question or would like to discuss a topic, give it a try! See ColorForums.com or below for more information. ** CHROMiX has expanded the FREE Eye-One Display 2 Offer. See details in ad below. ** Learn how to get $200 off of your next Eye-One purchase by trading in your old device and software! See details in Ad below. ** Delta-E - the color difference - an article written by CHROMiX President Steve Upton ==================================================================== Table of Contents =================
1. CHROMiX News
CHROMiX News ================ Since our last ColorNews Issue #16 (December 22nd, 2004) here are some of the 'happenings' at CHROMiX worth mentioning: CHROMiX is proud to announce that we are recently certified to install and train on several popular RIP and other software products including Onyx, EFI Colorproof XF and Caldera. We also sell ColorBurst RIP, GretagMacbeth ProfileMaker, Monaco Profiler, ColorThink (of course!) and several others - and provide consulting for them as well! Give us a call to discuss your needs. CHROMiX has instituted a new policy that all of our customers will appreciate. Drum roll please..... 'CHROMiX ColorGear will now match any legitimate price from any legitimate competitor on any product we sell'. Even though our pricing has always been considered aggressive (or even the best overall value), there are competitors around who sell on price only but don't support the product or provide anything pre-sales or post-sales. We feel very strongly about providing the highest quality pre-sales and post-sales support you need, and will never change that. Now there's assurance that you will get the best price as well as our great support. There will be a mention on the website stating this policy publicly.
We are excited to announce a new working relationship with eVolve, a great Seattle-based training group. eVolve has the people, skills and experience we've been looking for in a training partner and we expect to work with them to offer their customers and our customers effective color management training in the classroom setting. Keep an eye on our website and theirs for more details of classes to come including the advanced color training you've been requesting.
This is the second month of operation for the CHROMiX ColorForums. We would like to thank everyone who has contributed. We're continuing to improve and refine the usability of ColorForums, and your comments are always appreciated.
Because of significant interest and positive customer feedback, we thought it would be helpful to post this again: Steve Upton is the featured speaker in a free QuickTime-based seminar sponsored by Apple and GretagMacbeth. You can find it here (free registration required):
Many customers mentioned strong interest in the X-Rite DTP-70 spectrophotometer to us because of its blinding speed, only to be idled in the slow lane by not being available. However, the DTP-70 is now shipping in limited quantities and it is living up to it's early reputation. Give CHROMiX Sales a call if you're interested in this great device - 866-CHROMiX Extension 1 or email sales(at)chromix.com for more information.
Color, Product & Industry News
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Effective January 1st, 2005, X-Rite lowered the prices of the popular Monaco Optix XR and Monaco Optix XR Pro by $50 each. Citing streamlined manufacturing efficiencies, the move effectively keeps the prices at the 2004 prices after applying a $50 rebate. The new list is $249 and $379 respectively. CHROMiX sells these for $219 and $349 respectively.
GretagMacbeth just announced a new program for purchasers of the new Eye-One Design Bundle (List $895, CHROMiX $795). This program allows the purchaser to also purchase one add-on module for 50% off. The add-on module choices are: Eye-One RGB Output Module (List $395, 50% @ CHROMiX $175), Eye-One Input (scanner only) Module (List $195, 50% @ CHROMiX $90), Eye-One CMYK Output Module (List $595, 50% @ CHROMiX $275) and the Eye-One Beamer upgrade (List $495, 50% @ CHROMiX $225). For more details, see
The WMU Profiling Review 2005 is out and worth checking out. The Review from Dr. Abhay Sharma at Western Michigan University is a consumer report of ICC profile making software and covers all major vendors including GretagMacbeth ProfileMaker 5, MonacoProfiler 4.7, Heidelberg PrintOpen, Pantone Spyder2PRO and many, many others. The WMU Profiling Review 2005 is available via
If you didn't make the 2004 PIA/GATF Color Management conference in Phoenix, you can buy a CD of the entire conference for $249 ($199 for GATF/PIA members). The CD contains 18 digitally recorded and indexed sessions, including Steve Upton's seminar 'Can You Print or Proof to a Standard?' Download the Order Form from GATF at:
For the first time in nearly 30 years, Pantone has substantially redesigned the Pantone Matching System formula guide. The 2005 formula guide includes color swatches that are nearly 25% larger for increased accuracy and visual reference when specifying and matching colors. The Pantone solid chips book, also redesigned, will provide designers with larger tear-out chips. The 2005 formula guide should set a new benchmark for color. CHROMiX carries Pantone products.
Quark has released a PSD Import plug-in for QuarkXPress 6.5. This long-over due Xtension software allows the import of native Adobe Photoshop files (.psd), with layers, channels, and paths intact, into picture boxes in QuarkXPress layouts. Quark also recently announced QXML (QuarkXPress Markup Language), which is Quark's open-source XML language that works with the standard DOM (Document Object Model).
Kodak announced an agreement to acquire Creo. Creo, which has more than 25,000 customers and offices in 30 countries worldwide, will enhance Kodak with an innovative and progressive digital pre-press product portfolio. Creo has also established significant relationships in the commercial printing industry. If it goes through, Creo's operations will become part of the Graphics Solutions & Services operating unit of Kodak's Graphic Communications Group (GCG). There is a webcast and more information by accessing the Kodak.com investors page at:
Adobe Systems Incorporated announced that leading advertising and branding agencies Ogilvy & Mather, DDB Worldwide, and Wunderman have adopted Adobe InDesign CS software, layout and design program that is a part of the Adobe Creative Suite. One wonders if having strong color management capabilities had anything to do with the decision? Probably.
Adobe has released Camera Raw 2.4 and DNG Converter 2.4 for Mac and Windows.
In 2003, it's estimated that a total of 276 billion pages were printed on narrow format inkjet and color EP printers (defined as 8.5" x 11" pages) according to a report published by I.T. Strategies (editor note, that's over 50 million miles!). They estimate that more than 50% of these pages (152 billion) were printed in color. They go on to say: By 2008, the percentage of color pages should increase to 62% (372 billion pages out of a total of 596 billion). These estimates do not include wide-format inkjet output, which is typically counted in square feet/meters, not pages.
Apple's recent Security Update for OS X 10.3.7 & 10.2.8 had some people curious as to what the ColorSync vulnerability involved was (is).
Speaking of ColorSync....
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SHOWS & EVENTS
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February 6 - May 15, 2005, Rob Galbraith is doing a 10-city seminar series entitled 'Just Show Me How Pro Tour'. The course is designed for Photographers who make a living with a digital SLR camera, and want to learn more about how to import, select, edit, archive and distribute their work. Price is $149 for a full-day. Register at
February 20 - 23, PMA 2005 and DIMA 2005 Orlando, FL at the Orange County Convention Center in Orlando, Florida. For more information:
March 17-19, 2005 Graphic Arts 2005. Charlotte Convention Center, NC. This recent trade show and conference brings in thousands of industry professionals from the Southern USA. View many highlights of the 2003 show and sign up to be reminded of the next show in Charlotte, NC.
May 23-26, 2005 Seybold New York.
September 9-15, 2005 PRINT '05 at McCormick Place Complex, Chicago, IL Because of its mammoth size and international presence, PRINT occurs only once every four years and will take the place of GRAPH EXPO and CONVERTING EXPO in 2005.
ColorFAQ - Delta-E - the color difference
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Delta-E - the color difference
You don't have to spend too long in the color management world before you come across the term Delta-E. As with many things color, it seems simple to understand at first, yet the closer you look, the more elusive it gets.
First, the term itself is confusing. It refers to the difference between colors, and if you're trying to matching colors this is considered an error. Delta means difference or change and E stands for error. So does that mean delta-E means change in error? no... just error... strange...
Anyway, what delta-E (dE) IS, is a single number that represents the 'distance' between two colors. The idea is that a dE of 1.0 is the smallest color difference the human eye can see. So any dE less than 1.0 is imperceptible (as in turn the lights off and head to the pub) and it stands to reason that any dE greater than 1.0 is noticeable (as in put the coffee on, we're going to be here a while). Unfortunately - and probably not surprisingly - it's not that simple. Some color differences greater than 1 are perfectly acceptable, maybe even unnoticeable. Also, the same dE color difference between two yellows and two blues may not look like the same difference to the eye and there are other places where it can fall down.
It's perfectly understandable that we would want to have a system to show errors. After all, we've spent the money on the instruments, shouldn't we get numbers from them? Delta-E numbers can be used for:
- how far off is a print or proof from the original
Delta-E 1976
So, a bit of history is probably in order. The L*a*b* colorspace was devised in 1976 (let's just call it Lab for short) and, at the same time delta-E 1976 (dE76) came into being. If you can imagine attaching a string to a color point in 3D Lab space, dE76 describes the sphere that is described by all the possible directions you could pull the string. If you hear people speak of just plain 'delta-E' they are probably referring to dE76. It is also known as dE-Lab and dE-ab (although I'm REALLY not fond of dE-ab as it implies that only the a* and b* color components are calculated and L* is left out)
One problem with dE76 is that Lab itself is not 'perceptually uniform' as its creators had intended. So different amounts of visual color shift in different color areas of Lab might have the same dE76 number. Conversely, the same amount of color shift might result in different dE76 values. Another issue is that the eye is most sensitive to hue differences, then chroma and finally lightness and dE76 does not take this into account (since Lab does not take this into account).
Difference vs Tolerance: if difference is a number showing how 'far apart' two colors are, tolerance is the meaning of the number. Setting a tolerance level (such as 2.0 dE76) defines what you will accept and what you will reject(reproduction tolerance). The available differencing equations will also produce different shaped 'tolerance regions'.
Delta-Lab and Delta-LCH
One type of difference calculation that some people use is delta-L, delta-a, delta-b (dLab). By breaking the error into its components you can sometimes get a feel for what might be causing the error. If the tolerance region for dE76 is described as a round sphere, then dLab is a square cube.
My favorite variation on this idea is delta-LCH. Remember that LCH is Lightness (the same one as in Lab), Chroma (the distance out from the neutral axis - saturation) and Hue (the angle/direction in the 360 degree range). If d-Lab is a box-shaped region then d-LCH is a wedge - like cutting a piece of a flat round ring or washer. The interesting thing about d-LCH is what it can tell you about inkjet behavior. Different LCH values can refer to different problems, for instance:
As the eye's sensitivity to hue, chroma, and then lightness differ, the tolerance region around each color that contains acceptable color matches is best represented by an rugby ball-shaped ellipsoid. The more modern color difference formulae use this ellipsoid shape and allow you, the user, to vary several different parameters to tune the numbers to match visual comparisons.
CMC l:c
In 1984 the CMC (Colour Measurement Committee of the Society of Dyes and Colourists of Great Britain) developed and adopted an equation based on LCH numbers. Intended for the textiles industry, CMC l:c allows the setting of lightness (l) and chroma (c) factors. As the eye is more sensitive to chroma, the default ratio for l:c is 2:1 allowing for 2x the difference in lightness than chroma (numbers). There is also a 'commercial factor' (cf) which allows an overall varying of the size of the tolerance region according to accuracy requirements. A cf=1.0 means that a delta-E CMC value <1.0 is acceptable.
A technical committee of the CIE (TC 1-29) published an equation in 1995 called CIE94. The equation is similar to CMC but the weighting functions are largely based on RIT/DuPont tolerance data derived from automotive paint experiments where sample surfaces are smooth.
Delta-E 2000 is the first major revision of the dE94 equation. Unlike dE94, which assumes that L* correctly reflects the perceived differences in lightness, dE2000 varies the weighting of L* depending on where in the lightness range the color falls. dE2000 is still under consideration and does not seem to be widely supported in graphics arts applications.
A few important points about delta-E calculations in general:
- dE calculations are based on colorimetry which means they are illuminant-dependent. Don't try comparing numbers calculated from colors viewed / measured under different illuminants.
Finally, which equation should be chosen and how should it be used?
- for basic / fast calculations, you can use dE76 but beware of its problems
Choosing the right tolerance (Billmeyer 1970 / 1979)
1. Select a single method of calculation and use it consistently
I realize that this article is one of the more technical that I have written but delta-E is one of those topics that is worth understanding, and it can take a little work. I have also simplified the daylights out of some of my explanations. This is intended as an introduction to the concepts and not a detailed reference work.
At the very least, the next time you hear someone spouting off delta-E values you can ask them which delta-E. If there's a long, confused pause then you'll know what you're dealing with.
For more information and the actual equations I suggest you consult the following sources as I did for this article:
Colour Engineering: Achieving Device Independent Colour - Edited by Phil Green & Lindsay MacDonald. Wiley. ISBN: 0471486884
Thanks for reading,
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FEEDBACK and FAQs
Entire Contents of CHROMiX ColorNews (c)2005 CHROMiX, Inc.
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GretagMacbeth ships Eye-One Match 3.2 |
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GretagMacbeth has released version 3.2 of their Eye-One Match software. This module includes the much-anticipated Digital Camera Module for profiling digital cameras. If you purchased an Eye-One Photo after December 15, 2004, a simple download is all that's required to start using this software (along with free registration) | |||||||
Link: http://na.i1color.com/index.cfm/MenuItemID/103/MenuGroup/USA%20%2D%20Eye%2DOne%20Products.htm
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X-Rite Shipping DTP70 in numbers |
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X-Rite is now shipping their DTP-70 spectrophotometer in volume. The DTP-70 (also known by the development name "Slingshot") is an X/Y scanning spectro that feeds letter and legal-size sheets and can read an entire ECI target in 3-5 minutes. Support for the DTP-70 is available today in Monaco Profiler 4.7 and later and ONYX and other RIPs. | |||||||
Link: http://www.chromix.com/colorgear/shop/productdetail.cxsa?toolid=1132
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GATF Color Management Conference dates set |
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The dates for the popular color management conference are December 4,5,6, 2005 in Phoenix AZ. A call for speakers has been issued so interested speakers should contact Gwen Martin at the GATF. Steve Upton of CHROMiX is serving a second year on the conference's advisory panel. | |||||||
Link: http://www.colormanagementconference.com/
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EIZO Shipping CG220 - AdobeRGB-gamut display |
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EIZO is now shipping in volume their new CG220 LCD display. the CG220 has three internal 14-bit LUTs for extra-fine calibration of grays but a remarkable new feature is the AdobeRGB (1998)-size gamut of the display. This large gamut allows full view of the more saturated colors available in the AdobeRGB working space used by many imaging professionals. | |||||||
Link: http://www.chromix.com/colorgear/shop/productdetail.cxsa?toolid=1142
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CHROMiX & eVolve offer Adobe CS2 Color Seminar |
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Free CHROMiX / Evolve seminar "Adobe Creative Suite 2: Achieving Consistent Color in CS2". Come learn about the color management process and new color management capabilities in Adobe Creative Suite 2. Using the suite's "nerve center" the Bridge, you can now achieve consistent color in Photoshop, InDesign, Illustrator, GoLive and Acrobat. Join us at Adobe's Seattle campus June 15 at 5:30 for cocktails, hors d'oeuvres and 6:00-7:30 for the seminar. | |||||||
Link: http://www.evolveseattle.com/seminar/colorsignup2.html
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CHROMiX & eVolve offer Color in Photoshop course |
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CHROMiX will be offering a new co-developed class entitled 'PHOTOSHOP DIGITAL WORKFLOW with COLOR MANAGEMENT'. It is a 6-hour workshop on June 21st from 9:30 am - 4:40 pm for $300, and will be held at the Seattle Evolve facility. | |||||||
Link: http://evolveseattle.com/train/mainclass/pshop.html#color
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Steve Upton to present IPA Webinar on Color Management |
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Steve Upton will be presenting a WebEx seminar for the IPA on "An Introduction to Color Management" on July 13, 2005. This is intended as an intro for designers and art directors. The registration page is not yet online. Watch the IPA and CHROMiX sites for more information. | |||||||
Link: http://www.ipa.org/
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ColorThink 2.2 beta available - bug fix & feature bump |
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ColorThink 2.2 beta is now available. In a free update to the current ColorThink software, we are fixing a number of bugs and folding in a few new features. One new feature is the ability to read Monaco Profiler Export and Session files and export them in the standard CGATS format that GretagMacbeth uses. So you can use ColorThink to convert Monaco Profiler readings for use with GretagMacbeth software. This also means you can use Profiler to drive the DTP-70 and then pass the readings through ColorThink and build profiles with GretagMacbeth. If you want to play with the beta, please go to our download page and take a look. (It will use your existing 2.x serial numbers.) | |||||||
Link: http://www.chromix.com/colorthink/download.cxsa
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GretagMacbeth announces ProfileMaker Publish Plus |
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GretagMacbeth just announced a NEW addition to the ProfileMaker v5 suite called PM5 Publish Plus which has all of the features of PMv5 Publish Pro, but includes the MultiColor Module for CMYK+N profile generation. Publish Plus is ideal for expanding the gamut of devices with six additional colors like Digital Printers, Analog Presses, and LFP devices. Publish Plus is targeted at Publishing, Textile Printing and Sign Markets. Furthermore, GretagMacbeth is offering a special introductory value of a FREE Eye-One Pro spectrophotometer and Device Link Module. They've also added an ROI (return on investment) calculator to their site that you will find linked on the following page. | |||||||
Link: http://www.chromix.com/colorgear/shop/productdetail.cxsa?toolid=1167
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Hoodman announces flat-panel hoods |
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Hoodman has announced a revolutionary new monitor hood that we hope will start shipping by the end of June. (we're taking pre-orders and will let people know when it starts to ship) This revolutionary new monitor hood will adjust to fit CRTs and Flat Panel monitors from 13" to 23" in size, and works especially well with the Apple Cinema Display. CHROMiX is taking pre-orders now and will make sure you get one of the first ones available. | |||||||
Link: http://www.chromix.com/ColorGear/Shop/productdetail.cxsa?toolid=1147
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CHROMiX ColorNews Issue#18 available -Chromatic Adaptation |
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CHROMiX ColorNews Issue#18 is now available. There are many product and technical updates and the article in this issue is about Chromatic Adaptation. | |||||||
Link: http://www.chromix.com/colorsmarts/smartNote.cxsa?snid=1168
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CHROMiX ColorNews Issue #18 - Chromatic Adaptation |
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Welcome to ColorNews, a periodic update on things related to Color Management. We are striving for a regular consistent newsletter of high value to our customers. Please let us know what your interests are so we can address these concerns in our coming issues. ============================================================= C H R O M i X C O L O R N E W S
Issue #18 ============================================================= Several Quick Notes of Interest: ** CHROMiX will be discontinuing the FREE Eye-One Display promotion after June 30th. See details below. ** Steve Upton and the CHROMiX tech gang have a new ColorThink software update coming very soon that will also have some very cool additional features. See details below. ** GretagMacbeth has a new version of ProfileMaker v5 available at an introductory special. See excerpt in Color, Product & Industry News below. ** Don Hutcheson has some revealing thoughts about Fuji discontinuing the Velvia 50 film in Tech Notes below. Also, be sure to check out Tech Notes #2 and #3 for two, very good on-line articles. ** CHROMiX has a special offer to all GIA 'Color Without Limits' seminar attendees. CHROMiX will give you $225 credit towards the purchase of an Eye-One solution. See Ad below. ** TRADE in that old device and get $80 to $200 off of your next Eye-One purchase! See details in Ad below. ** Chromatic Adaptation - an article written by CHROMiX President Steve Upton ==================================================================== Table of Contents =================
1. CHROMiX News
CHROMiX News ================ Since our last ColorNews Issue #17 here's what's going on at CHROMiX: (busy as usual) Our new working relationship with eVolve, a great Seattle-based training group is, well, eVolving. There are two new events to tell you about:
Free CHROMiX / Evolve seminar "Adobe Creative Suite 2: Achieving Consistent Color in CS2". Come learn about the color management process and new color management capabilities in Adobe Creative Suite 2. Using the suite's "nerve center" the Bridge, you can now achieve consistent color in Photoshop, InDesign, Illustrator, GoLive and Acrobat. Join us at Adobe's Seattle campus June 15 at 5:30 for cocktails, hors d'oeuvres and 6:00-7:30 for the seminar. For registration and more information follow this link:
We will be offering a new co-developed class entitled 'PHOTOSHOP DIGITAL WORKFLOW with COLOR MANAGEMENT'. It is a 6-hour workshop on June 21st from 9:30 am - 4:40 pm for $300, and will be held at the Seattle Evolve facility. We would love to have you join us. For more details follow this link:
Steve Upton will be presenting a WebEx seminar for the IPA on "An Introduction to Color Management" on July 13, 2005. This is intended as an intro for designers and art directors. The registration page is not yet online. Watch the IPA and CHROMiX sites for more information.
ColorThink 2.2 beta is now available. In a free update to the current ColorThink software, we are fixing a number of bugs and folding in a few new features. One new feature is the ability to read Monaco Profiler Export and Session files and export them in the standard CGATS format that GretagMacbeth uses. So you can use ColorThink to convert Monaco Profiler readings for use with GretagMacbeth software. This also means you can use Profiler to drive the DTP-70 and then pass the readings through ColorThink and build profiles with GretagMacbeth. If you want to play with the beta, please go to our download page and take a look. (It will use your existing 2.x serial numbers.)
ColorNews is now available in the RSS newsfeed format. CHROMiX will be using the RSS feed capability to post updates and announcements to our website and any RSS newsfeed subscribers. What this means to you is that CHROMiX will devote a part of our website to a live news feed of Color Management and related industry news - so you'll only need to go to one place to get any and all relevant information. If you have upgraded your Mac to Tiger, RSS reading is available as part of the new Safari. Just go to our website at Click Here and click on the blue RSS icon on the right side of Safari's location bar. To directly link to the feed file go here:
The CHROMiX ColorForums are growing in popularity and usage. Thanks to everyone who contributes and participates. ColorForums.com is the first full-featured online forum dedicated to color management tools, techniques and support. Not only is there a clear web-based interface to all forum topic areas, but it is backed up with a comprehensive email system. You can read and post messages via the web or email, so those of you who don't always have time to surf the web can have the color management community come to you. If you have a technical question or would like to discuss a topic, give it a try!
==================================================================== Color, Product & Industry News ====================
Apple just released Tiger, it's new Mac OS X operating system software. Mac OS X v10.4 (Tiger) has some very cool features: Spotlight, Dashboard, Automator, iChatAV, and nearly 200 other new features. Tiger appears to be a very good product. However, as with every new operating system, there are a number of incompatibilities with existing software products, drivers, dongles, etc., until developers arrive at Tiger compatibility. Color management seems to have also changed a bit with Tiger. Look below in our Tech Tips section for Tiger tips.
Adobe has released Creative Suite 2 (CS2). CS2 is a dramatic improvement over CS1 and touts easier use and powerful new features. CS2 also has a more consistent and robust color management functionality when moving from Photoshop to Illustrator to InDesign. Plus, you can synchronize your color settings (and other stuff) from one location in Bridge Center, a new centralized file browser. Cool. There is a new 'safe' CMYK color management for InDesign & Illustrator users to ensure the CMYK isn't mishandled. CS2 also ships with a new Euro profile based on Fogra standards. Here are some great reviews from CreativePro.com:
GretagMacbeth just announced a NEW addition to the ProfileMaker v5 suite called PM5 Publish Plus which has all of the features of PMv5 Publish Pro, but includes the MultiColor Module for CMYK+N profile generation. Publish Plus is ideal for expanding the gamut of devices with six additional colors like Digital Printers, Analog Presses, and LFP devices. Publish Plus is targeted at Publishing, Textile Printing and Sign Markets. Furthermore, GretagMacbeth is offering a special introductory value of a FREE Eye-One Pro spectrophotometer and Device Link Module. They've also added an ROI (return on investment) calculator to their site that you will find linked on the following page. For more information:
GretagMacbeth has also released version 3.2 of their Eye-One Match software. This module includes the much-anticipated Digital Camera Module for profiling digital cameras. If you purchased an Eye-One Photo after December 15, 2004, a simple download is all that's required to start using this software (along with free registration): Fujifilm is releasing a new set of Fuji input/scanner targets. The new Fujifilm Color Targets II are a kit of 5 Fujifilm IT8.7 targets. Four targets are IT8.7/1 (transmissive targets) including 2 35mm format (Velvia, Provia), 2 4x5 format (Velvia, Provia); the 35mm targets are accompanied with batch-read colorimetric data, while the 4x5 targets include custom-measured colorimetric data. The remaining target is an IT8.7/2 (reflective target) made on Fujifilm Crystal Archive Paper (Type DP). Targets are not available for sale individually, only as the complete kit. CHROMiX will be reselling these kits when available.
Hoodman has announced a revolutionary new monitor hood that we hope will start shipping by the end of June. (we're taking pre-orders and will let people know when it starts to ship) This revolutionary new monitor hood will adjust to fit CRTs and Flat Panel monitors from 13" to 23" in size, and works especially well with the Apple Cinema Display. CHROMiX is taking pre-orders now and will make sure you get one of the first ones available. For more information:
Printers are seeing increased printing activity on average as opposed to slowing down. The Printing Business Index (PBI) of the National Association for Printing Leadership (NAPL), the Association's broadest measure of print activity, rose to 60.1 in March 2005, up from 57.8 in February and 59.0 in January. Rising costs are tempering this progress a bit and providing a new challenge. For more: ==================================================================== Tech Notes ====================
#1 We asked Don Hutcheson how Fuji's discontinuation of the Velvia 50 film would affect the HutchColor HCT products. Here's what Don said:
1) The method of sampling the curves is flawed by the fact that they do not measure pure dyes, but rather a developed dye image produced by exposing the films with narrow-band R, G and B light. Unfortunately there are no wavelengths that exclusively stimulate each layer without some cross-talk into the others, so the curves for the dye in one layer may well include some residual absorbencies happening in the other layers, which falsely indicate a different color dye. What ultimately matters is how well a target on one emulsion reproduces images on other emulsions. In my experience a profile made from the current Velvia HCT works very well on a variety of Fuji transparency materials, as well as on other emulsions, like Ektachrome, but this depends a lot on the scanner filter curves. I have no plans to make a separate HCT on Velvia 100, as I have not seen the need and Fuji 8 x 10 film is getting hard to buy in small quantities" Thanks for the update, Don!
#2 Greg Exelby pointed out a great on-line article that we thought we'd share with you: PAPER & INK FAQ's, by Sabine Lenz. With all the great proofing technologies available these days, is there still a need for designers to come to press checks? If you are a designer, this is a very valuable read. If you're a printer or broker finding that it's impossible to keep creatives out of the pressroom, this article will highlight the need for taking the initiative to educate your customers about the behind-the-scenes work that goes into their print job. The link:
#3 There is another very good article by Charles Pickett of Publish that discusses a possible new approach to the problems occurring while soft-proofing in variable ambient lighting environments. A must read. #4 Mac OS X (10.4) Tiger seems to be producing some color-related problems that we are monitoring: - some users are reporting that ColorSync monitor profiles are not travelling between users when Fast User Switching. If you see this problem, try trashing the "com.apple.colorsync.profiles" files from the "/Library/Caches/" folder. Also, put profiles in the /Library/ColorSync/Profiles folder and they will be available to all users on your system.
- if you are having problems with your HASP-brand dongles under Tiger you may want to download the new drivers:
#5 A great review of ColorEyes Display has been posted to the Luminous Landscape site. It reinforces what we have found ourselves: ColorEyes Display is good stuff!
SHOWS & EVENTS ================
June 6-9, 2005 Seybold Amsterdam. Click Here
June 7-9, 2005 IPA Technical Conference, Westin O'Hare, Rosemont, IL. A conference with focus on the latest trends, tools and techniques for graphics professionals. This event will highlight a Color Proofing RoundUP, a Workflow RoundUP, Keynotes from some very notable industry leaders, and a management track as well.
June 12-15, 2005, NAPL & PIA/GATF Sheetfed Pressroom Conference at Marriott O'Hare Hotel, Chicago, IL General sessions and specific seminars will address managerial and technical issues relating to current Sheetfed Pressroom topics and concerns.
June 23, 2005, 6 - 9 PM, Portland, OR. PDF Wine & Tasting Faire, presented by the Pacific Northwest Color Management Users Group. This event focuses primarily on PDF, and secondarily on PDF Color Management issues. Many vendors and consultants will be there, including Adobe's Peter Constable. The event details and location are available at:
July 19-23, 2005, Las Vegas, NV, The Creative Suite Conference. Join leading Creative Suite experts in the largest Creative Suite (CS2) training event of the year.
September 9-15, 2005 PRINT '05 at McCormick Place Complex, Chicago, IL Because of its mammoth size and international presence, PRINT occurs only once every four years and will take the place of GRAPH EXPO and CONVERTING EXPO in 2005.
ColorFAQ - Chromatic Adaptation
============================================================= First, a few corrections. Thanks to those who wrote in with the "what the..!?" questions. 1. In ColorNews Issue #16 I cut off a sentence mid-way leaving you all hanging... sorry about that. The sentence should have been: "This way he (Joseph Holmes) would bypass the potentially destructive scanner->smaller workingspace or workingspace->workingspace conversions. (he actually went further than this by creating a number of these color spaces which allow shrinking the gamut of an image by simply assigning different profiles)" 2. In ColorNews Issue #17 I incorrectly stated that delta-E stood for delta-Error - I am happy to say that it does not. The E stands for "empfindung" a German word for sensation. Change in sensation makes much more sense! So, on to this issue's article: Chromatic Adaptation
hocus-pocus? As the color management world works its way toward version 4.x profiles we find that we're getting more and more questions about the differences with v4 profiles and what they mean. One important difference is that all profiles (except device links) are now required to have a 'chad' tag (chromatic adaptation). So what is chromatic adaptation? It's probably best to take a step back and talk about how colors are calculated and the different flavors of Lab. The Lab colorspace (more correctly written L*a*b* but who wants to do that all the time) is based on human perception and is typically calculated from spectral reading curves combined with human eye response curves (observer) and an illuminant (lighting) curve. While we can change the observer and illuminant curves, most Lab colors are based on the 'standard 2 degree observer' and the D50 illuminant curve. To be precise, the flavor of Lab used in Photoshop, ICC profiles and most other publishing cases is the "2 degree, D50" Lab and it's fair to assume that "Lab" written on its own is 2 deg D50 Lab. (it doesn't hurt to ask though) If all our lighting conditions matched the spectral curve of D50 we'd be set. Unfortunately many don't even come close. In fact, it's impossible to reproduce D50 using any man-made light source! (see my article in issue #14 of ColorNews for more) In most situations, for instance, we recommend calibrating CRT displays to the D65 white point to better match office lighting and sometimes even 5000K light booths (see ColorNews #2). Also, neutral colors printed on inkjet printers achieve their tones by the careful balance of CMYK inks. This balance is calculated for a specific spectral lighting curve and may shift considerably under different lighting (sometimes called metamerism - see ColorNews Issue #5). While we try to build profiles that minimize this effect, sometimes we're better off calculating the color numbers for the profile using a totally different illuminant curve. ColorNews past issues: Click Here In order to calculate colors based on a different illuminant, we just substitute the new illuminant curve into the "spectral-reading (times) observer (times) illuminant" equation we use to calculate Lab (it calculates XYZ from which we then calculate Lab). So if we substitute the spectral curve for the D65 illuminant then we get a color number representing the measured sample under the alternate lighting. The important thing here is that it is now '2 degree D65 Lab'. As we rarely change the observer, let's just call it D65 Lab. While this flavor of Lab is quite useful it should never be handed to ICC profiling tools as they typically expect D50 Lab numbers - the ICC spec specifically states that all measurements will be D50 Lab. So what do we do? Chromatic Adaptation. This series of matrix calculations will convert colors that are relative to one white point (D65) to be relative to a new white point (D50). Without this essential conversion we are handing the profiling software (and the profile, and ultimately the CMM) the wrong numbers and we will probably be disappointed with the result. "But wait!" you say "if we wanted D50 numbers, why didn't we just calculate Lab using the D50 illuminant in the first place?". The answer, as I hinted above, is metamerism. The spectral makeup of D65 lighting can change the appearance of certain dyes and pigments significantly. So the color we get from calculating Lab using D65 and then adapting it to D50 can be noticeably different than calculating the D50 Lab color directly from the measurement.... Do you see where this leads? In one calculation we get D50 Lab numbers as illuminated by a D65 light source and in the other, D50 Lab numbers as illuminated by a D50 light source. Now we can correctly calculate delta-E values and assign some numbers to the metamerism / gray balance failure problem we often see! This "metamerism index" can be handy in evaluating inksets and predicting what sorts of problems we're going to see when our gallery-viewed photograph (3500K Solux Lamp) is purchased and moved into an office (6000K fluorescent with nasty spectral spikes). Another challenging situation is the color data within profiles. As I mentioned above, all measurements within profiles (or handed to profiling applications) are in D50 Lab. If the original measurements were not D50 Lab and were adapted to be D50 Lab then we need to know what flavor of Lab they were originally if we have a hope of reconstructing them. Why would we want to reconstruct them? Well, WE might not but CMM developers might (CMM is Color Management Module, the actual software that converts colors within your applications or OS). We (all of us using ICC profiles) are currently in the age of the "smart profile" and the "dumb CMM". This means that most color conversion smarts are built - hard coded - into profiles. When the CMM converts our colors from one profile to another, it does not do much analysis at all. Most calculations are concerning interpolating colors, which is fairly basic on the scale of things. Future CMMs, however, could do more analysis of the source and destination profiles, image data, etc. In order to do some of these advanced calculations, it can be helpful to be able to reconstruct the original measurement conditions. The 'chad' tag in v4 ICC profiles is required so that any chromatic adaptation calculation that created the profile's colors is documented and available to the CMM if it needs to "back calculate" any colors during its conversions. The good folks at the ICC are hoping that this will help in situations where conversions had broken down in the past. So we have covered three specific situations where chromatic adaptation may be used:
- converting non-D50 Lab values to D50 Lab for profiling applications Are you going to use chromatic adaptation in your color pursuits? Perhaps. Most often these calculations will be performed by profiling software on your behalf. If you are doing color calculations for use in profiling software then you may need it. If you are trying to get your arms around metamerism and want to compare measurements under different lighting conditions then you will definitely need it to calculate delta-E values. I've built chromatic adaptation calculations into our upcoming ColorThink Pro software to save you some of the pain of relearning your linear algebra and to do quick metamerism checks. (And yes, I had to relearn my linear algebra.) At the very least, you now know more about this calculation and when to watch out for incompatible color numbers. You also have new terminology to firmly establish your geek-hood at cocktail parties. Thanks for reading,
Steve Upton
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= In a visit to CHROMiX.com or profilecentral.com, you opted to receive this newsletter. You may have also heard Steve Upton speak and requested more information. If you have received this message in error, we apologize. We value our relationship with you and do not want to spam you. See below for details on how to provide feedback, how to unsubscribe, or how to become a sponsor.
2 ea used Monaco Optix XR (New $219) $175 <-- price drop 1ea X-Rite DTP-22 Digital Swatchbook (serial) $499 <-- price drop 2ea Fuji (ColourKit) Monitor, RGB Output Profiler & Image Processor software bundle. New. $299
Entire Contents of CHROMiX ColorNews (c)2005 CHROMiX, Inc.
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CHROMiX Launches ColorThink Pro |
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Seattle, WA (Sept 7, 2005) - CHROMiX today announced significant new product based on award winning ColorThink software. CHROMiX is a member of the Color Management Group and will be demonstrating ColorThink Pro in the Color Management Group booth #8633 at Print05 ColorThink Pro offers enhancements to 3D color graphing and ICC color profile analysis. Also introduced is a ground-breaking Color Worksheet tool for workflow modeling and color analysis, and the new ColorCast profile technology. "Our ColorThink toolset is used by every major imaging company in the world, as well as color consultants, trainers, prepress technicians and photographers" explained Steve Upton, CHROMiX CEO and President. "As you can imagine, we've received a long and varied list of feature requests over the years. ColorThink Pro is the first in a new level of professional-grade tools that offers many of the advanced analysis and trouble-shooting tools that are needed today." A color managed workflow involves multiple color conversions using several ICC profiles. If the resulting colors are not satisfactory, it can be difficult and confusing to isolate each color conversion and determine where the problem lies. The Color Worksheet allows the user to lay out the workflow graphically and use images or color measurements to illustrate where the problem lies. But the Color Worksheet's utility doesn't stop there. Any list of profiles (including device, abstract and link types) can be bonded together to create device link abstract or standard device profiles. Linking existing device profiles to other profiles is a radical and powerful new technology called ColorCast that offers solutions to several sticky color problems around today. ColorCast profiles capture complex color transformations such as proofing a 6-channel press and embed them inside regular workingspace and device profiles which can be used anywhere - see technology announcement for ColorCast, also announced today. Tying all of this together is the ColorSmarts Guide. A combination automator and teacher, the ColorSmarts Guide is like having a color consultant standing over your shoulder. Select from over 20 tests that are built into the Guide, and it will perform them for you and present the results as a graph, worksheet or delta-E report. ColorThink's graphing and profile analysis abilities have been expanded as well. Graphs can now be saved as movies or sessions, and include gridlines and a sectioning tool called the Slicer. The Profile Inspector adds dot gain curves, gamut volume calculation, and ink statistics. ColorThink and ColorCast have patent-pending technologies and CHROMiX has engaged the firm of Schwabe, Williamson & Wyatt (www.schwabe.com) as our intellectual property representatives. ColorCast and ColorThink Pro were both announced this week at the Print05 show in Chicago. (see related release for more ColorCast information). Drop by booth #8633 for a look or contact Carolyn Boone for an appointment. About CHROMiX CHROMiX was founded in 1998 to provide technical services and products to businesses in content-production industries. We have dedicated our efforts to color management and image fidelity and have combined an excellent suite of tools with many years combined industry experience. We feel we are uniquely qualified to serve our customers. Much of our business takes place in the US but we regularly provide products and services internationally and have customers, dealers and partners in over 95 countries. Press Contacts
Steve Upton
Carolyn Boone |
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CHROMiX Announces ColorCast Technology |
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Seattle, WA (Sept 7, 2005) - CHROMiX today announced ColorCast, a new color simulation and modeling technology used with ICC color profiles. ColorCast technology alters ICC profiles by embedding color transformations into normal ICC device profiles. The result is a profile that is usable with any ICC compatible system but contains complex proofing or modeling transformations. Photoshop, the CS2 suite, Quark and Freehand don't support Hexachrome® or other multicolor printing systems directly. End-users with the need to soft and hard-proof multicolor workflows are faced with the additional expense and confusion of plugins which aren't available for many of the professional publishing or desktop applications people use. "ColorCast technology is remarkable because, while there is considerable color wizardry going on under the hood, the resulting profile is still a regular ICC-compatible print, scan, or monitor profile." explained CHROMiX president and ColorCast creator Steve Upton. "As a result, soft and hard-proofing of multi-color and abstract profiles is now available in ANY application, print driver or RIP that supports ICC profiles." Multicolor printing is expanding every year and has seen significant inroads in the packaging industry. One challenge faced by printers is communicating the advantages of multicolor printing to their clients and allowing them to simulate final expected results. ColorCast profiles can be created to capture the effect of a complex multicolor printing system (up to 10 channels) within a client's working space or printer profile. The client can use the profile in a wide variety of applications to simulate final color. Rendering intent choices select the simulated profile's intents, allowing full flexibility. The technology can also be applied to input and working space profiles. A digital camera profile could be combined with effect or utility profiles increasing contrast or modeling a film type. Working space profiles can combine with abstract profiles to inherit their abilities and still remain standard profiles supported in Photoshop. ColorCast technology appears in the ColorThink Pro application (also announced today) and may appear in other applications in the future. ColorCast contains patent-pending technologies and CHROMiX has engaged the firm of Schwabe, Williamson & Wyatt (www.schwabe.com) as their intellectual property representatives. ColorCast and ColorThink Pro were both announced this week at the Print05 show in Chicago. Drop by booth #8633 for a look or contact Carolyn Boone for an appointment. About CHROMiX CHROMiX was founded in 1998 to provide technical services and products to businesses in content-production industries. We have dedicated our efforts to color management and image fidelity and have combined an excellent suite of tools with many years combined industry experience. We feel we are uniquely qualified to serve our customers. Much of our business takes place in the US but we regularly provide products and services internationally and have customers, dealers and partners in over 95 countries. Press Contacts
Steve Upton
Carolyn Boone |
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CHROMiX ColorNews Issue #19 - Color Management Myths 26-28 |
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Welcome to ColorNews, a periodic update on things related to Color Management. We are striving for a regular consistent newsletter of high value to our customers. Please let us know what your interests are so we can address these concerns in our coming issues. ============================================================= C H R O M i X C O L O R N E W S
Issue #19 ============================================================= Several Quick Notes of Interest: ** FREE CHROMiX Color Management Utility Kit when you buy either an Eye-One Pro solution or an X-Rite Pulse ColorElite solution. See ad below.
** Big Price Drop on GretagMacbeth Eye-One products AND a further $200 off Eye-One solutions?? ** Purchase an Eizo ColorEdge LCD monitor and get either half off a ColorEyes Display bundle, or get one absolutely free!! (offer varies depending on monitor model) This bundle is valued at $319, and is currently the most highly regarded LCD monitor calibration software & instrument on the market. See detail below. ** Got an old Eye-One? Wishing you could justify the purchase of one of the new ones with all the bells and whistles? Well, now's the time! GretagMacbeth, in discussions with CHROMiX, is preparing to launch it's new Customer Loyalty Program! ** 3 more Color Myths - an article written by CHROMiX President Steve Upton ==================================================================== Table of Contents =================
1. CHROMiX News
CHROMiX News ================ Since our last ColorNews Issue #18 on June 2, here's what's going on at CHROMiX: Rick Hatmaker of CHROMiX wrote an article for Digital Imaging Techniques (August issue) evaluating the GretagMacbeth Eye-One product line as well as the the X-Rite Pulse ColorElite solution. You may find this useful if you're shopping for either product or looking to upgrade. Find the article at: Click Here
Anne Taylor of CHROMiX will be speaking at this year's BioComm conference on July 24th in Portland, OR, about color management and workflow for the field of BioCommunications. Interestingly, most conference attendees are using the Adobe Creative Suite and have overwhelmingly requested color management as a key focus and emphasis. Workflow and color management are particularly problematic in the Biocommunications field due to the wide range of input and output devices used in medicine and the life sciences.
We've had a big price drop on Eye-One Photo, Proof, XT and others. Nothing like a summer sale!
CHROMiX is continuing to offer the training class 'PHOTOSHOP DIGITAL WORKFLOW with COLOR MANAGEMENT'. It is a one day workshop being held August 18 and September 21, from 9:30 am - 4:40 pm, at the Seattle Evolve facility, for $300. Recent attendees have mentioned how effective this class was for them. It could be for you too. Please join us. For more details follow this link: Steve Upton's Webinar for the IPA "An Introduction to Color Management" on July 13th was very well received! If you missed it, you can still catch part two of this Color Management for the Creative Community series. Part two is called 'Photoshop and Color Accuracy', and is scheduled for Wednesday, August 3rd at 1:00 PM Eastern. Steve will cover Photoshop essentials for accurate color matching, including:
- Manage missing profiles when opening files
For more information, or to register:
ColorThink 2.2b15 beta is now available. It is a free update to the current ColorThink software. We continue to add fixes and look for feedback from our users. Download a copy, give it a try, and let us know what you think. CHROMiX at Print05 in Chicago. Yes we'll be there and we'll be showing off new versions of our software. We haven't determined which booth we'll be in yet so stay tuned! (we'll have a newsletter before Print05 giving all the details)
Steve Upton of CHROMiX is serving a second year on the GATF conference's advisory panel. The dates for the popular color management conference are December 4-6, 2005 in Phoenix AZ. A call for speakers has been issued, so interested speakers should contact Gwen Martin at the GATF.
The number of users and topics of discussion continue to grow at our ColorForums website. Check it out if you are looking for answers to technical problems. It's free! Finally, please let us know how you like the new ColorNews RSS Feed service on our home page. We welcome your feedback.
Color, Product & Industry News ====================
GretagMacbeth Customer Loyalty Program - this is just being finalized as we "went to press".
GretagMacbeth has released the long-awaited ProfileMaker Packaging software. This extension to the ProfileMaker line is intended for the particular challenges of the packaging industry and includes the ability to create n-color profiles (profiles where the ink is in any order, up to 10 channels) and their patent-pending GOP profiling technology. GOP (Generic Output Profiler) allows the replacement of an ink, and the recalculation of the profile without having to perform an additional press run. This is going to be a boon for the flexo market. GretagMacbeth will have product information as well as an interactive training piece available on their site within the next day or so:
In June, IPA announced the results of the 2005 Color Proofing and Workflow RoundUP. EFI ColorProof and GMG scored well for Proofing, and other RIPS were not far behind. Dr. Abhay Sharma, author of Understanding Color Management and a respected professor at Western Michigan University, conducted the event. The results are available on a CD for a nominal fee, and is well worth it, as this is one of the more legitimate product comparisons you'll find.
Unless you live in a cave you probably already know this... Adobe is planning to buy Macromedia. More details at Apple has announced the plan to shift processor supplier from IBM to Intel. On June 6, 2005 Steve Jobs announced this decision at his Keynote speech at Apple's 2005 Worldwide Developer Conference. The first Intel processors should ship with Macs starting in 2006 and the entire product line should be running Intel by 2007. (All CHROMiX software products will be supported on the new platform.) Microsoft announced PowerToy, an upcoming RAW viewer add-on for Windows XP that enables the handling of Canon and Nikon RAW formats directly within Windows. Microsoft will also be adding extensive RAW format support through a codec architecture for Longhorn, the next major release of Windows due in 2007. ColorBurst will announce (on Friday 7/22) version 4 X-Proof and X-Photo RIP software that will support the Epson 4800. They will have an FTP site for downloads. ColorBurst mentioned that a free updater will be posted to the their website next week. ColorBurst has also recently been approved as part of two SWOP certified proofing systems on both Mac and PC platforms. This is the fifth SWOP certified proofing system for ColorBurst in the last two years. GTI, maker of controlled lighting and viewing stations, has introduced several new models which reflect the ongoing shift toward wide-format and digital imaging. They have expanded the VPI Vertical Print Inspectors to include vertical (poster) format. GTi has also added the availability of rotary controlled dimming or digital dimming on their 24", 36", and 48"" overhead luminaires.
SHOWS & EVENTS ================
September 8-10, 2005, PMA Fall Imaging Conference and Mini Trade Show at Manchester Grand Hyatt, San Diego, CA.
September 9-15, 2005, PRINT '05 at McCormick Place Complex, Chicago, IL Because of its mammoth size and international presence, PRINT occurs only once every four years and will take the place of GRAPH EXPO and CONVERTING EXPO in 2005.
September 11-14, 2005, Seybold Chicago at Hyatt Regency McCormick Place, Chicago, IL.
September 28-29, 2005, Digital Imaging '05 at Hyatt Regency San Francisco Airport, CA.
September 28 - March 1, 2005, SGIA Specialty Printing & Imaging Technology Show, New Orleans, LA.
November 29 - December 2, 2005, Seybold San Francisco at The Palace Hotel, San Francisco, CA.
December 4-6, 2005, PIA/GATF Color Management Conference at The Pointe Hilton Tapatio Cliffs Resort, Phoenix, AZ. This is the only US show with exclusive focus on color management technology. Hear about the latest tools, workflows, and trends in producing high-quality color.
ColorFAQ - 3 more Color Myths
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=-=-=-=-=-=-=- Myth #26: Graphing profiles to see their gamut gives pretty much the same results in the different tools that are available. =-=-=-=-=-=-=- ColorThink plots gamuts using the device->Lab (ie CMYK->Lab) "proofing" part of the profile. Like when you soft proof, we ask the profile "if I send 100% Cyan, what color will I get?" - only we ask it for a large number of these colors and we get a good estimation of the behavior of the device. If you built the profile yourself and have access to the original measurements, you can plot them along with the ColorThink profile gamut and they will match up quite closely (if it's a good profile). When we do this "proofing" conversion we use the absolute colorimetric rendering intent which gives us accurate paper whites and ink blacks. The ONLY way to show the actual gamut of the _device_ is to use the Absolute Colorimetric intent when calculating. This pulls the white down to paper-white and shades it accordingly. None of the methods of viewing profiles in the ColorSync Utility allow this. The ColorSync utility allows you to view the "gamuts of profiles" by either clicking on them in the profile list (which shows the perceptual mapping) or clicking on the various A2Bx tags when you open a profile. When you click on these tags in the profiles, the CSU shows you the perceptual, saturation and relative colorimetric gamuts. What do they represent? well, they show how colors in device-space (CMYK, RGB, etc) will appear when converted through the profile. Does this mean anything? sort of, but only to a very experienced user. People typically want to know 1) how is my device performing and 2) how is my profile performing when printing? (which is the opposite, Lab->device conversion) So, ColorThink answers #1 (and is the only grapher I know of that does it this way, why I don't know) and graphing a color list or image and applying a profile to get vectors answers #2. The CSU doesn't answer either of these questions... not that what it's doing is technically incorrect.... well perhaps it is: - each "unit" in Lab is supposed to represent the smallest color shift the eye can see - in any direction (lightness, saturation, hue). The lightness axis L goes from 0-100 while the a and b axes go from -128 to 127. This means the box defined by the ICC for Lab is not a cube but is wider than it is tall. There is no valid reason to stretch the vertical L axis to be the same size as the widths of a and b but many graphers do this including the CSU... This results in "tall" gamuts and ColorThink's are "flatter". As far as I can determine, flatter is correct yet most other graphing tools I've seen stretch the Lab space into a cube, producing tall skinny gamut volumes that don't make sense (at least to me) Other graphers like Monaco, GretagMacbeth and others plot what I call the "rendered gamut" of profiles (as opposed to the device gamut). Using this method, Lab values are converted through the profile to device colors and then back to Lab. If very saturated colors are chosen at the outset then this round-trip method will squish them into gamut and then a gamut volume can be graphed. This volume can be useful but does not describe the device behavior alone - it really shows what the profile will give you if used to print to the device (and specifically how the very saturated colors will print). This may seem like splitting hairs but it's not. Many printers receive CMYK files separated by unknown profiles. A device gamut will describe the maximum space these images can occupy, a rendered gamut will not and, in fact, some image colors may appear outside of the rendered gamut. Another way to think of this is with the example of ink limiting. If you build a CMYK profile that has a total ink limit of 200% you will probably limit the gamut of files printed using that profile. When graphed in ColorThink you will see the gamut of the device, all the way up to 400% coverage. In other tools you will see the rendered gamut, which will be smaller, especially in the darker colors. ColorThink Pro, which we are working on right now will allow both graphing methods so you can compare the profile's printing capabilities with the device's overall capabilities. The "normal" ColorThink will continue to graph device gamuts. They are the simplest to understand and jibe well with graphs of the device measurements used to build the profile. A bit long-winded I know but that's the way it is with color..I hope this helps. =-=-=-=-=-=-=- Myth #27: Why would anyone ever want to choose a working space that is larger than you can print? =-=-=-=-=-=-=- This is a classic question and one that we receive only slightly more often than "Why does my printer keep recommending such small working spaces?" The roots of these schools of thought are in the perspective of each user and how they tend to want to recommend (push) their workflow to other people. In studying color reproduction challenges over the years, I have broken workflows down to three distinct groups (I am exaggerating them a little): - Input Centric - this is where people want to capture as much of the original film (or scene) as possible. They choose large working spaces (much larger than the monitor gamut) and archive high-bit images for the day when printers catch up with their desires. Monitors, printers and presses are necessary evils that all degrade the appearance of their work. If they have the ability they will fill a whole CD with one scanned image. You might guess that this is where photographers often reside. - Output Centric - this is where the final print is the deciding factor in workflow decisions. Working spaces like ColorMatch are considered plenty big enough to contain all the colors one would want to print. So working spaces are chosen that will contain the gamut of a press and nothing more. Much of their work is done in CMYK (in-gamut by definition) and they wonder why anyone would bother capturing color that can't be printed. As you can imagine, prepress and printing folks are in this group. - Display-Centric - this is where people just want what's printed to match what's on the screen. Computer artists, 3D artists, video editors and consumers tend to fall into this group. All work headed for the web also falls in this category. sRGB is typically chosen as the working space as it tends to match the display gamut fairly closely. It doesn't contain any more colors than the display can show so there are fewer surprises. The truth is that each of us will find ourselves in these different roles at some time. There's nothing wrong with being in any of the groups and people may change groups depending on their budget or project. It's fair to say, however that folks who are entrenched in any one group have a lot of trouble understanding the other groups. Ever try to get an offset printer to try to understand your photographic decisions? or vice versa? So if John is an "Input Centric" and your are an "Output Centric" you will probably never see eye-to-eye on working spaces AND you may each be using spaces that are good for your respective pursuits. In color management there is often no single correct way to do things. What we do suggest is a few things that will apply to all:
- choose a working space that is just large enough to contain your imagery; any bigger and you're wasting space. =-=-=-=-=-=-=- Myth #28: The PowerBook G4 displays 16.7 million colors (or any display, for that matter) =-=-=-=-=-=-=- This is not true. Don't confuse RGB number combinations with the number of perceivable colors. I can send 16.7 million different RGB NUMBER combinations to a PowerBook display (3 channels with 8 bits per channel) but it will only display 518,733 different colors. This means that 16,258,483 of the RGB numbers are basically "wasted". Another way of looking at this is to say that the entire gamut of 518,733 colors is chopped into 16.7 million separately addressable "chunks". Problem is, the difference between each of these chunks is smaller than is perceivable by humans. So if you glom chunks together until each blob is just barely perceivably different than the next, you'll end up with 518,733 of them. That explanation is a bit of a stretch but sometimes it helps to break these things down to understand them. (pun intended) This confusion is another example of the difference between RGB and CMYK values and actual colors. Another example of this is with CMYK devices. I can send 100,000,000 CMYK values to print on newsprint (100x100x100x100). Does that mean I'm going to get that many actual colors? No, of course not. If I send those CMYK values to a sheet-fed press on glossy coated paper will I get that many colors? No, but I'll get more than I did from newsprint. I'd probably see even more from an inkjet. While I can address the colors on a press using CMYK combinations, each CMYK combination will not produce a unique color. Thanks for reading,
Steve Upton
For previous ColorNews articles follow this link: =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
Entire Contents of CHROMiX ColorNews (c)2005 CHROMiX, Inc.
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