CHROMiX ColorNews Issue #13 - Color Management Myths 11-15 |
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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 #13 =============================================================
** The transition of ProfileCity into CHROMiX is continuing to prove beneficial to customers. If you're an OEM Manufacturer or Distributor (Ink, Paper, Printer, etc.), be sure to read the section devoted to Licensing below. ** ProfileMaker Pro version 5 is a MAJOR release and has a lot of far-reaching ramifications (end-user benefits, the competitive marketplace , GretagMacbeth's continuing health and success, and more). Read the special section below to get up to speed on ProfileMaker v5. ** If you're considering an Upgrade to ProfileMaker v5, don't miss the 20% EXTRA special savings, but ONLY until June 30. See advertisement details below. ** It's almost over! The very popular FREE Eye-One Display promotion ends June 30, 2004. See details below. ** '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 #12 (April 26, 2004) many things have happened at CHROMiX that are worth mentioning: CHROMiX welcomes the addition of Anne Taylor to our group of partner consultants and trainers. Anne has an extensive history of production, training and technical support in high-end prepress. She has worked for a number of high-quality prepress groups, consulted to many well-known imaging companies and most recently worked with Corbis. At Corbis Anne set file submission standards, color management workflows, and trained and supported internal personnel and external photographers and customers in digital imaging. We are excited and honored to have someone of Anne's capability on our team and are already applying her talents to our customers!
As part of working with Anne Taylor, CHROMiX is now offering WebEx-based training to our customers world-wide! Our first course offering is "Color Management in Photoshop" and we will be offering courses in other areas in the future. WebEx allows us to bring you the expertise of people like Anne Taylor, Steve Upton and others at a fraction of the cost of having them come to you. If you are interested in this training, please contact Rick in sales for more details.
Adobe has named and featured CHROMiX ColorThink as the primary toolset for organizing, modifying and visualizing profiles in their May 2004 Color Management issue of 'ReadMeNow', a periodic tech newsletter for Adobe Solutions Network Service Providers (ASN's). For more information on ASN, go to
Apple has listed CHROMiX ColorValet Profiling Service in their latest ColorSync June 2004 white paper, called 'Color Management in Mac OS X Panther'. You can download the FREE 24-page pdf from the ColorSync website at
Apple has sponsored and published a new book in the Apple Pro Training Series called 'Color Management in OS X: A Practical Approach' by Joshua Weisburg. CHROMiX ColorValet Profiling service is featured prominently throughout the book. Even better, our ColorValet Print Profiling Kit is available on the CD that is included. Although the book is not available yet, you can pre-order at Amazon.com for $30.59.
CHROMiX is taking the integration of ICS's ProfileCity custom profiling operations to new levels. With recent efficiency increases, our service turn-around time is dramatically improving. Our obsession for high quality profiles can now be translated into quicker turn-arounds for you. Give us a try and find that a great profile delivered quickly makes all the difference in your color world!
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.
Success breeds success! Color Management adoption is growing at an astounding rate these days. However, it is still only a small fraction of its huge potential. Sign up and Partner with CHROMiX to take advantage of this growth potential and also create additional revenues, or offer Color Management products and services to your customers.
** Steve Upton will be speaking at the following events:
July 14, 2004, 6PM - 7PM Macworld Boston. Steve will lead a Q&A discussions group at the Birds of a Feather Color Management session. At this event, current users of Color Management may pose questions & open discussions about current color management trends and new technologies and products. One topic will be Apple's upcoming ColorSync certification program for consultants and color professionals. If you're a current user of Color Management and at MacWorld Boston, don't miss this one:
July 15, 2004, 2PM - 3:15PM Macworld Boston. Steve will be speaking at MACWORLD Boston, MA. Steve will provide a complete Color Management overview, with focus on the concept and purpose of ColorSync profiles, device gamut's, display calibration, printer profiling and how to fit it all together in Adobe Photoshop. He will also cover the evolution of ColorSync in OS X. This is a great session for photographers, designers, art directors, printers, or anyone else trying to get a handle on their digital imaging system.
Color, Product & Industry News
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GretagMacbeth has finally released and is shipping Photostudio Pro and most modules of ProfileMaker version 5 profiling and color management software. ProfileMaker Publish Pro should ship this week, June 14th. Having beta tested ProfileMaker for GretagMacbeth, CHROMiX is excited about the new features, including custom target generation, enhanced multi-color profile and a significant upgrade to the camera profiling module. See the special ProfileMaker v5 section below for more details.
GretagMacbeth completely re-designed and enhanced their main www.gretagmacbeth.com website. The new website includes more detail on on all products and technology - including Munsell products, online products, Sequel technology and professional services. It also includes a Color Management Solutions finder, an online Support Center, updated information about the company, a color library with general color information, and more.
EFI announced Best Designer Edition 4.0, an update of its desktop color proofing software. Scheduled for release in June, the update will feature a new Mac OS X and Windows operating platform for greater flexibility in a variety of proofing environments, support for HP's CMYKplus standard for color management, compatibility with JDF 1.2 (an open standard for electronic job ticketing), plus support for the Epson Stylus Pro 4000, the HP Designjet 30 and 130, and more than 30 other inkjet printers.
Good news ...
More good news ...
At Drupa, GretagMacbeth announced:
++ Expanded iCPlate II family of plate readers from GretagMacbeth delivers fast, easy-to-use, and accurate plate reading QA for conventional and CtP plates -- New entry-level, cost-effective iCPlate II Basic joins original iCPlate II Advanced model to round out family of solutions that include a high resolution, auto-calibrating plate reading device, a test target, software to transfer measurement values to any Windows application and new optional plate quality control software.
... and for many of our customers, our favorite 'future' GretagMacbeth product teaser:
++ GretagMacbeth announces the Eye-One iO at Drupa 2004 - - upgrading the award-winning Eye-One family to affordable scanning automation. This scanning chart reader, with its revolutionary new design, brings hands-free, ease-of-use, and affordable automation to Eye-One Pro.
At Drupa, X-Rite announced three new products:
DTP-70 - "Slingshot" - A DTP-41 on steroids? Perhaps a closer comparison would be to GretagMacbeth's ICColor. Feed a strip-style target into the Slingshot and it will measure the entire target (x,y). The Slingshot is probably the fastest instrument of its type on the market, reading an IT8 target in less than 3 minutes. OK, it's not on the market yet but it's on its way.
Intellitrax - An auto-scanning press-side color scanner and reporting system that includes the instrument and touch-screen-based computer system. Features include the ability to read an entire color bar in less than 15 seconds, X-Rite's "look ahead" technology that helps it find and navigate color bars, and the instant display of data while readings are still underway.
Nifty flash intro with pictures:
Drupa tends to bring products out of the lab and onto the trade show floor earlier than most shows so we are still researching these products and their actual delivery dates are unknown at this time. We'll keep up on them for you and let you know when they make it to market.
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SPECIAL Section: ProfileMaker v5
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New Features and Differentiations:
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If you are distributing profiles that were created using a commercially available profiling software (e.g.: GretagMacbeth, Monaco, Fuji, Kodak, ColorVision, ColorBlind, ICS, PraxiSoft or others) and they are for "OEM" purposes (i.e.: Ink, Paper, Printer manufacturers, RIP manufacturers, distributors, etc.), be aware that you are probably violating the software license agreement with that software manufacturer if you have not negotiated and paid for additional licensing. People may not be aware of the profiling software restrictions that they acknowledged when registering their software. However it is illegal to make and sell profiles made from all software for OEM's use. Most profiling software companies have OEM licensing programs available. The downside is that these are rather steep, and usually only the largest of companies can afford to play.
Except CHROMiX. We have negotiated and are authorized to license profiles to OEM's, thankfully, because of our unrestricted usage and access to ICS profiling software. Known as world class profiling software, this software was used to make profiles for Profile City. CHROMiX now has the ability to offer the most competitive OEM license arrangements anywhere and you don't need to be a large company to take advantage of these licenses.
If you're an OEM who needs profiles for your products (Ink, Paper, Printer Manufacturer, RIP Manufacturer, Distributor or other), please feel free to contact us to discuss how we can help you and your profile needs. Find out why CHROMiX is regarded as the Premier Profiling Service in the world because of our obsession for the highest quality standards in our profiles. For more information or to discuss your color management or profiling needs, call:
TECH NOTES
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Achromatopsia (Color Blindness)
SHOWS & EVENTS
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June 17 - 19, 2004 Gutenberg 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 in 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 and hosting a Birds-of-a-Feather session.
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.
August 16-19 , Seybold San Francisco, 'From Concept to Reality', Moscone West, San Francisco, CA.
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. 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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Join me in discussing five more color management myths - there seems to be no end to these! Follow the links at the end of the article for the previous 10 myths.
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I cannot tell you how many times we see this happen. It sounds simple enough, really. Print a profiling target to your printer with all color management turned off. Send the target off to CHROMiX to have a profile built for you or build one yourself using your own equipment. To test the profile, reopen the original profiling target in Photoshop and print it through the profile.
Anyone see the flaw, or flaws in this approach?
It sounds like it should work but there is a subtle yet very important function occurring that renders the printed result useless for testing anything but grays. When you print your profiling target originally, no color management is to occur to the pixels in the target. So a 255,0,0 RGB Red will print the PRINTER'S VERSION of 255,0,0 Red. No problem. When you look at the print, the colors seem saturated & pure and seem like they'll build a good profile. (they typically do).
When you reprint the target through the profile, Photoshop has to assume a source color space for the profile. After all, if you are converting TO your new print profile you have to convert FROM something right? (remember, profiles are always applied in pairs) So Photoshop is now assuming that 255,0,0 RGB Red is Adobe RGB red (or whatever you're using as your working space). It is important to note that Adobe RGB's 255,0,0 Red is typically quite a different color than your printer's 255,0,0 Red. That's why you need to build and apply your printer profile in the first place. Adobe RGB 255,0,0 Red sent directly to your printer doesn't look right. (that's why the original profiling target print probably didn't match the target displayed on your monitor).
So when Photoshop converts your 255,0,0 Red from Adobe RGB through your print profile it gets the closest red your printer can supply. This is NOT going to be the same red as the printer's version of 255,0,0 red. To help understand this think of two triangles, one overlaying the other but rotated 15 degrees or so. Your Adobe RGB 255,0,0 is at the tip of one triangle and the printer's 255,0,0 red is at the tip of the other. They're both reddish but definitely not the same - Adobe RGB's red is oranger than the printer's. When Photoshop uses profiles to match, the profile will "move the Adobe RGB red in" toward gray until it hits the first color the printer can print. (think of sliding in toward the center of the Adobe RGB triangle until you hit the edge of the printer's triangle). This will result in a slightly orangy red that is less saturated than Adobe RGB's full 255,0,0 red but fairly hue and lightness-accurate.
Can you see the problem now? You (unknowingly) asked the printer profile for it's closest match to Adobe RGB red. It might have given you a pretty good match but if you are visually comparing to the original printed target's 255,0,0 red you will find they do not match at all! They are not supposed to!
My example of 255,0,0 Red is obviously only one of millions of possible colors, all of which will probably not match! The only exception is the neutral grays. Grays in your working space SHOULD create grays on paper. This can be a pretty good test but the gray patches are often surrounded by colors that throw off your perception and so are hard to judge. If you want to print targets to evaluate grays, use targets which have the grays isolated and be sure to view them under controlled lighting.
A final point to this lengthy description is that the human eye does not do well with patch-to-patch comparisons. Our eyes evolved their color discrimination judging good food from bad and sick people from healthy, among other things. Use real-world pictures of people, food and other natural scenes to judge color accuracy. You will see a subtle magenta shift in dark skin (one of my favorite tests) or a greenish tint in meat way before you will ever see it in color patches of the same colors.
Targets are for computers, pictures are for people.
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Most inkjets in use today use more than 4 inks when printing. (I can say this with some confidence as Epson seems to have over 2/3 of the market and all their printers have more than 4 inks).
In most of these printers, Cyan, Magenta, Yellow and Black inks are joined by light-Cyan (Lc) and light-Magenta (Lm). When lighter, highlight colors are printed, the lighter versions of Cyan and Magenta are used (Yellow is light enough to not typically require a lighter version), Black is almost totally shut off and it becomes very difficult to see any dots. This makes the inkjet appear to print at high resolution and can create smooth color transitions.
>From a more technical "channel control" perspective, the Cyan and Magenta channels are fairly normally behaved. The hues of the light Cyan and light Magenta inks are closely matched to their darker siblings. Imagine printing a "wedge" from 100% ink to white. As the printer moves from 100% dark ink through the midtones it adds progressively more light ink and removes dark ink. When it moves up into the highlights, the darker ink is removed entirely and only light ink remains until it is removed entirely and you finally reach paper white. This behavior is usually transparent to the user although in some RIPs you can control how and where the transitions occur. Either way, it is transparent enough that the blending occurs independently of any color profiling that may occur.
So, as far as profiling is concerned, these are 4-hue printers and we typically make either CMYK (if a RIP is available) or RGB profiles (for normal driver control).
The addition of "light black" (as Epson likes to call it) to some newer printers also does not affect channel control in profiling. Epson has recently introduced a true 6 color printer to their line, adding Red and Blue inks. This printer, along with other true 6-color printers might be profile-able as more-than-cmyk printers but a good RIP that gives full access to all the color channels is still required. For those using manufacturer drivers, RGB is still the type of control we have and the profile that we build.
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OK, so perhaps we don't think about this consciously but we all do it. Grab a print and bring it closer to your face to see the details better.
A little physiology and color history are in order. First, those wonderful color-sensing cones in our eyes are concentrated in an area of your retina called the fovea. Your thumbnail at the end of your arm makes an angle of entry into your eye of about 2 degrees and roughly within your fovea. It makes sense that as you move your thumbnail (or a print sample) closer to your eye, it makes a larger image on your retina and the mix of rods (black and white only) vs cones under that image changes significantly. Does this mean your color perception of it changes as well? Yes in fact, it does.
This "thumbnail" sizing is pretty rough but not a bad visualization. I've done some quick calculations (who said I'd never use trig) and found that I need either shorter arms or fatter thumbs to get 2 degrees but I'm sure you get the idea.
Anyway, color profiling technology today is based on machines attempting to "see" colors as the human eye does. This is achieved in part by using "standard observer" information from the CIE that shows us how the human eye responds to light. There are two main standard observer types: 2 degree and 10 degree. As you might be able to guess, this means we can calculate colors based on the "thumbnail at the end of your arm" size of retinal image or a significantly larger "thumbnail at about 4 inches" size. I've done some color differencing calculations and found that colors can differ by many delta-E in some cases.
So remember that the size of the image in your eye plays a part in color matching. Using a larger lighting booth that requires you to stand a few feet back from your prints is a good idea. Also, if you do large-format work and want to print small samples for proofing, do not print the entire image shrunk down to fit on your proofer's page! Print a chunk of the final work that will fit on your proofer page but not be reduced in magnification. Otherwise you'll be playing optical tricks on yourself that will not result in happy customers.
I don't know about you but the word Brightness to me means, well, brightness. How light or bright something appears to my eye. Related perhaps to how much light it gives off. Contrast (to me) is how much of a difference there is between the light areas of an image and the dark ones.
On CRT monitors however, they don't mean that at all. The Contrast knob controls how brightly white and the lightest colors will appear. It sets the maximum amount of light the screen will produce (also called gain).
The Brightness knob on a CRT controls how light the darkest shadow colors are. Known as bias to engineers, it controls where/when the guns "turn on" to create the first step of gray above black. These are both very important controls when calibrating your monitor but they've always seemed mislabeled to me.
Now that we are moving headlong into the world of flat-panel displays it pays to pay attention to how things work in "LCD land".
What I have found on most non-laptop LCD displays is the disappearance of the Contrast control. The Brightness control is still available and controls the output of the backlight system.
This means that the Brightness control changes the total light output from the display. Yes, this is the job of the Contrast knob on CRT's. So contrast on CRTs becomes brightness on LCDs and brightness is gone!
I'm happy to see that the Brightness control on an LCD has a name that finally makes sense but concerned that this all happened without any notification or explanation. I don't know about you but I didn't get the memo!
I suppose Myths 14 and 15 fall into the "just thought you should know" category.
Thanks for reading,
Steve Upton
Please see ColorNews Issue #9 for the first 5 myths:
Please see ColorNews Issue #11 for the next 5 myths:
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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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