Color management--art or science?

Color management-art or science? Perhaps, it is a combination of both. Today, color management remains one of the more challenging aspects to digital reproduction. Color must be controlled for accurate output, and several companies provide software systems and measurement tools to aid digital workers in this endeavor. Is it achievable via automation without human intervention? Some experts describe the task as a series of dilemmas. One such "pessimist" is Gary G. Field, imaging scientist and professor at California Polytechnic State University, who comments, "The first dilemma that faces developers of color management systems is how to compress input tone and saturation values to fit the color gamut offered by the output recording system.

"A 'perceptual' compression strategy that retains a tonal and saturation separation in the reproduction similar to that possessed by the original is often quite successful for the less-demanding branches of the consumer market. These automated compression strategies, however, often fail when used for the more demanding graphic arts applications. The reason for such failures is computer systems are incapable of choosing the 'interest areas' of the original that are most prized by human observers when viewed within a particular context," he observes.

"Another dilemma facing the developers of color management systems is even more difficult than the first: In most cases, people will choose 'preferred color' over 'accurate color.' The paradox here is a given reproduction may require that a product be accurate, but that other colors within the same image are reproduced in a preferred--rather than accurate--fashion. Sometimes, however, accurate color is chosen over what is usually a preferred color. Caucasian skin tone reproductions, for example, are preferred 'more tan" in most circumstances. On the other hand, they must be accurately reproduced in such cases as a skin cancer detection guide," Field suggests.

"Color films routinely incorporate 'preferred' color distortions to suit consumer markets. Selective alterations to such preferences are made both to incorporate the art director's aesthetic vision and to accurately reproduce critical colors. These kinds of common graphic arts 'corrections' require human judgment; color management is well out of its depth here," he continues.

"Yet, other problems, not unique to color management, have always plagued the process of graphic arts color reproduction--the behavioral and economic factors surrounding the color approval process. The source of such issues derives from the critical nature of the 'Proof OK' process. The proof is prototype of possibly millions of production images; therefore, careful scrutiny of the proof for possible errors or color distortions is essential.

"Companies employ print buyers, art directors, and others whose responsibility include proof approval. It is a quirk of human nature that, if responsibility for exercising judgment is assigned to an individual, this person will tend to exercise the authority to make changes, if for no other reason than to prove that judgment is being exercised. An automatic 'OK' may, after all, raise doubts about the diligence of the person who makes the color approval judgments," Field concludes.

Does this mean color management users are faced with the choice of either a "perceptual" or "colorimetric" approach to the problem? Probably not, since several color management systems have put together powerful colorimetric tools that can automate the task. Human tweaking, however, may always be necessary for the reasons stated above by Field. Among the leading developers of color management systems, Monaco Systems Inc., Andover, Mass. (www.monacosys.com), and X-Rite Inc., Grandville, Mich. (www.xrite.com), have teamed up to offer a cost-saving professional software/tool bundle that includes the MonacoPROOF program and X-Rite color measurement instruments. Called the X-RiteColor Ensemble for Color Management, the package is priced at $3,500 and $3,600, a saving of $1,300 over individual component purchases. In addition to MonacoPROOF, included are the X-Rite Monitor Optimizer and the advanced DTP41 AutoScan Spectrophotometer, which offers single-button operation with high-speed automation (more than 900 color patches in less than 10 minutes). Monaco offers a complete line of ICC-profiling products, including MonacoEZcolor, MonacoPROOF, and MonacoPROFILER, each of which is designed for different audiences. One of the company's recent products is MonacoEZ for Macintosh OS X; and MonacoPROFILER 4.5 now supports Windows 98/2000/XP, with a Macintosh upgrade for OS X available in mid-October.

Bill Owens, worldwide product marketing manager for Digital Imaging, Photo and Medical at X-Rite, comments: "As digital proofing continues to rise in acceptance, the demand for tightly integrated color management solutions is increasing. Users often struggle with putting together disparate color management solutions, which is time consuming and costly. X-RiteColor Ensemble Solutions eliminate the headaches involved in piecing together color management by providing the industry's most reliable, accurate, and cost-effective tools and software in a simple, affordable package."

GretagMacbeth, Regensdorf, Switzerland (www.gretagmacbeth.com), is another company that offers a professional line of color management systems. At the top is its new high-end color management tool kit, ProfileMaker Professional 4.1, designed to create and edit color profiles of a wide variety of scanners, monitors (including flat-panel LCD displays), digital cameras, printers, and multiple-color output devices for up to seven-channel printing. The software operates with GretagMacbeth color measurement instruments, as well as equipment from other companies.

For more entry-level digital assignments, GretagMacbeth has the more affordable and user-friendly Eye-One color management systems, which range in price from $600 for profiling monitors to $3,000 for a full-featured system. Recently, Gretag-Macbeth expanded the Eye-One tool's versatility with Eye-One Share, which permits extended color communication capabilities to several digital color professionals, who are not equipped with the measuring device. Another new Eye-One tool is the palette browser, which has the ability to browse through the entire color space and select any color the user wishes to import into Photoshop (or other imaging programs) though drag-and-drop commands. The software supports Windows operating systems, as well as Apple's latest OS X. The Eye-One system has its own website at www.i1color.com. Recently, Electronics For Imaging Inc., Foster City, Calif. (www.efi.com), introduced the EFI Color Profiler, engineered by GretagMacbeth, based upon Eye-One technology. The instrument permits the creation of custom profiles in workflow environments.

Heidelberg USA Inc., Kennesaw, Ga. (www.us.heidelberg.com), has an extensive Linocolor suite of Coloropen ICC products designed to optimize workflow. Included are: Scanopen ICC, which produces input profiles; Printopen ICC, which creates output profiles; and Viewopen ICC, which generates monitor profiles. Also integrated into Linocolor software is ICC Profile Editor, which enables users to adapt any ICC input, monitor, or output profile to devices using both LCH and CMYK corrections. Linocolor's Softproof feature also provides real-time WYSIWYG visual control for manipulating image color on monitors and output, and Geo Assistant will automatically recognize originals in job generation.

Imaging Technologies Corp., San Diego, Calif. (www.itec.net), released new versions of ColorBlind Professional and ColorBlind Matchbox (www.color.com). The products can be purchased as stand-alone applications or bundled color measurement devices, and with or without color management training at ITEC's ColorBlind Academy. The advanced ColorBlind Professional system costs from $4,799 to $7,100, depending on what type of instrumentation is included. The more economical ColorBlind Matchbox is designed for smaller digital imaging operations and can establish ICC color-managed workflow for input and output devices, as well as monitors. The software-only version is $645, while instrumentation packages run from $1,345 to $1,995.

Praxisoft LLC, Sterling, Va. (www.praxisoft.com), offers the $999 WiziWYG Pro kit that includes the $599 WiziWYG Deluxe hardware monitors calibrator, as well as the ColorSavvy ColorMouse colorimeter, which offers the ability to profile printer output. The company has a wide range of color management systems and tools, including CompassProfiler for out-of-the-box profiling of scanners and printers, and it supports leading spectrophotometers. ICC AutoFlow is production software that recognizes embedded images within EPS and Postscript files, and is able to color manage these elements.

Eastman Kodak Co., Rochester, N.Y. (www.kodak.com), markets Kodak Colorflow Custom Color ICC 2.0, an Adobe Photoshop plug-in that provides profile-editing ability. The software requires no instruments to fine-tune high-quality color results using existing ICC color profiles from monitors and output devices. It permits corrections that are not possible in CIELAB, the Profile Connection Space (PCS), and can make adjustment locally or globally. Using Photoshop tools, color regions can be modified without affecting the neutral gray balance.

Pantone Inc., Carlstadt, N.J. (www.pantone.com), partnered with ColorVision, Inc., Lawrenceville, N.J., (www.colorvision.com), to create the LCD/CRT Spyder, a colorimeter specifically targeted towards professionals who require a more affordable color management instrument, such as pro photographers and designers. It is priced from $260 to $450, depending on the software bundle selected. The seven-filter device is available with four different software packages: PhotoCAL, Photo Suite, and Photo Suite PRO for color professionals profiling their monitors and printer output; and OptiCAL for calibrating multiple monitors. In addition to major color management equipment manufacturers' websites, there are several retailer sites devoted to profile making and editing, including ProfileCity, Encinitas, Calif., (www.profilecity.com), which markets software such as its own Profile Manager, as well as providing custom-made profiles for customers; and Chromix, Seattle, Wash. (www.chromix.com), that sells its own ColorThink 1.1 profiling software, as well as serving as an online retailer for most other color management suppliers.

Tips for selecting a color management system

During the past two years, color management developers have made major improvements in their products. Overall, today's crop of recently introduced software and instruments are more affordable and easier to use than earlier technologies.

Color management system purchasers must responsibly review their company's goals and requirements, as well as estimate future growth potential, before deciding on a system. Obviously, different users have different needs. For example, a design studio working with a single desktop proofer may only require a low-cost system for calibrating its monitor and printer output. On the other hand, a digital service bureau with multiple workstations and a wide variety of input and output devices will require a more comprehensive color management solution. Digital workers should know the differences between the two primary instruments for color management--spectrophotometer and colorimeter. The spectrophotometer measures color by breaking light into a spectrum of color bands and measuring each band. The GretagMacbeth Eye-One and the X-Rite DTP41UV Auto-Scanning Spectrophotometer are such devices. The colorimeter only filters light to determine a number of color ranges, without reducing it down to the spectrum level. Advantages of colorimeters are: (1) they are more than adequate for many applications, (2) they generally require less service compared to the more complex and expensive spectrophotometers. The Pantone ColorVision Spyder is a colorimeter.

Finally, color management profiling of devices must be an on-going procedure--it's not a one-time event. For example, the profile of a printer's output will probable change with new inksets or a switch in media. As devices age, the stability of their performance will vary, producing changes in color profiles.

"In most cases, people will choose 'preferred color' over 'accurate color.' The paradox here is a given reproduction may, require that a product be accurate, but that other colors within the same image are reproduced in a preferred--rather than accurate--fashion."

--Gary G. Field, imaging scientist and professor California Polytechnic State University