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Seeing What You're Getting Will Get Easier

By Kathleen Maher

The digital age has transformed the creation of commercial art but when it comes to color, digital displays have brought uncertainty and doubt to even the most confident artist. After years of trial and error the print industry and the display industry worked out an awkward working relationship based on the sRGB color space and CRTs but then along came low-cost, lightweight LCD monitors and the game had to start all over again. CRTs can display more colors and they have a better gray scale so they could reproduce color more accurately than most LCDs on the market. It's not surprising that many artists in all fields have maintained a death grip on their old CRTs.

The arrival of wide color gamut LCD displays is changing the situation once again and by early 2010, artists will have a number of choices and price points from which to choose but it has been a long road to get to this point. Several factors have had to come in to play and several major players have had to push the technology forward. First of all, there are the graphics processors in computers -- they had to be able to support wide gamuts of colors. They've been capable for years now, but the LCD displays based on CCFL (cold cathode fluorescent lamps) backlights were not up to the challenge. More recently, LEDs (light emitting diodes) have come down in price. White LEDs enable brighter screens and more colors; better yet, RGB LEDs expand the amount of available color, and both white or RGB LEDs are a vast improvement over CCFL. Finally, there is the connector -- the computer and display have to be able to communicate all the color information. Enter DisplayPort and HDMI. The HDMI connector is primarily used for consumer electronics devices including TVs, while DisplayPort becomes the standard for PCs. Display port allows for increased resolutions, higher refresh rates and deeper color depth.

The Hewlett Packard DreamColor put all the pieces together. It was not the first wide gamut color display on the market, Sony and NEC were there first and others have piled on, but the HP DreamColor, priced at $3499 was the first affordable wide gamut color display with color management. And now, the all skate sign has been turned on. There are already over 60 different displays advertised as "Wide Gamut" for sale today and their prices range from $289 to over $11,000. They can have white LEDs or RGB LEDs but what will define their usefulness for digital content creation will be their color management ability. Having access to more colors is a huge part of the problem but being able to adjust those colors to be what you want to see is the final challenge.

The DreamColor color management system was developed in conjunction with Portrait Displays, a company which develops software for all kinds of displays including televisions and computer displays. As a result of that work, Portrait Displays has developed Photo Tune wide-gamut software. Photo Tune software is embedded in the monitor's firmware and it eliminates the need for hardware calibration and let's people select the proper color spaces on the fly. Several monitor companies have adopted Photo Tune. In addition, other monitor makers are developing their own approach to color management. The new year 2010 will usher in a new generation of monitors that will once dramatically improve the ability of artists to see what they're really trying to see.

As a consumer, however, it's important to know what to look for in a monitor. First of all, it has to be a wide gamut monitor. Your computer's graphics processor has to support 24-bit color. That usually means you need a discrete graphics processor rather than an integrated graphics processor. It has to have DisplayPort (or, less likely, HDMI). And, it has to have color management technology. Does it allow you to choose color space options?

Put it all together, and it spells the end of the dark years of early LCDs.

A word about color spaces

The computer display can not possibly display all the colors perceptible to the human eye, but the CIE 1931 color wheel is an attempt to represent the visual spectrum. It is the standard for what the display should at least strive for. The standard RGB or sRGB color space was created by HP and Microsoft for use on computer displays, printers, and the Internet. Thanks to sRGB, there is at least polite agreement among computer displays, printers, and the Internet. Adobe RGB was developed by Adobe to extend the gamut to include CMYK colors. Although, there are slightly more colors included in Adobe RGB, it is primarily a shift that takes in more greens and deeper reds. Most digital cameras now support Adobe RGB.

Figure 1: Conceding that no color display existing today can display all the colors visible to the human eye, color spaces claim their territory out of the CIE 1931 color spectrum. In a comparison of sRGB and Adobe RGB it’s more important to note what color ranges they encompass rather than the number of colors. The goal is color accuracy.

In addition to sRGB and Adobe RGB, there are other color spaces including Apple RGB for CMYK color printers, SMPTE-C for movies, Rec. 709 for HDTV, NTSC 1953 for early color TVs, and DCI-P3 for digital cinema. Displays often define themselves according to color space. Unfortunately, it’s rarely the same color space. Thus, you have Dell promising 117% of NTSC and a LaCie monitor promising 95% of Adobe RGB. And, to make matters worse, display manufacturers often set retail monitors to a color space that displays highly saturated colors so the monitor will look great in the store an environment with harsh fluorescent lighting. They don’t look so great when they get home unless you recalibrate the monitor – a task made much easier if you can change the color space.

Buying a new monitor is just the first step to better color reproduction on an LDC display, and luckily a lot of great options are on the way. But, it’s also important to understand color spaces so that you have a consistent way to see the most accurate colors achievable on the monitor you have bought.

This article originally appeared at Communication Arts magazine.

Kathleen Maher is vice president at Jon Peddie Research a consultancy based in Tiburon, California, specializing in multimedia and graphics. Maher is the author is several influential research studies including reports covering Digital Content Creation and Computer Aided Design.