Scary epiphany of the day: color management is like doing laundry.
For a little effort, such as separating your reds from the rest, you get a large return: nothing turns pink. Put in a little more effort--pull out the whites, and they won't become grays. But take it one step further, such as separating your darks into various hues (I do blue, green and brown, black, and red as separate loads), and the visible improvements start to diminish, despite the extra work. So you decide how much time and effort you want to put into sorting the wash and balance it against what you'll accept in the colors.
The same holds true for color management. For a little bit of effort and no extra cash, you can take a big step toward getting printed or displayed colors reasonably close to what you expect. If you spring for basic color-management software and make informed hardware choices, you'll get even closer. Throw increasing amounts of time and money at the problem, and you get increasingly closer to the ideal. The real issue with color management is finding that happy intersection between time and money spent and personal satisfaction with the results.
Unfortunately, like laundry, color management is also a tedious task that few of us can avoid.
Much of what I'll talk about in upcoming columns--photo printers, inks and paper, retouching images, scanning slides, and working with RAW file formats--relies on mastering a lot of the same concepts as those for color management, so I'm going to spend a few columns building the foundations before tackling the subject in more depth. (Don't worry: I'll be covering other requested issues, such as organizing your photos.) But I know you guys are more about practice than theory, so I'll also try to provide some useful advice in every column as well.
Thirteen quick fixes
If you're impatient to start getting better output color immediately, I herewith provide these suggestions, sans verbose explanations, and in no particular order.
- Always make sure you have the latest printer and display (graphics card and monitor) drivers, as well as the most current ICC profiles for your hardware.
- When available, always use the color profile specific to the paper type. It should go without saying that you always choose the appropriate paper type in your printer driver.
- Characterize and calibrate your monitor and printer about once a month.
- Always work under the same lighting you had when you calibrated.
- Install some daylight lamps or full-spectrum light bulbs in your studio. Don't try to judge color accuracy under standard fluorescent or very warm incandescent light.
- If your camera or camcorder supports it, manually set white balance when you shoot. And for digital cameras, shoot RAW if possible.
- Don't believe the myth that color management doesn't apply to video. Want proof? Take a look at the video on this page. My shirt and my skin aren't those colors. Unfortunately, color matching for video on the PC is even harder than for print.
- Accept the fact that if you use third-party papers, you're going to waste a lot of it--and a lot of ink--before you get the right settings.
- Always use the Print Preview option in your printer driver. It doesn't guarantee that the print will come out right, but it helps cut down on the prints that come out wrong.
- Unless you like exchanging bright, saturated colors for accurate ones, try not to use the sRGB color space.
- Consider that the colors you're trying to produce may not be within the gamut of the output device (see lesson 1 below).
- Most image-editing software these days, regardless of target market, has some type of color management in it. The difference among them rests with how much control the program gives you for changing the options. If you're having problems getting the colors you want, it may be because the software is constraining your choices. Try switching to a more flexible program, such as Jasc Paint Shop Pro or Ulead PhotoImpact. Alternatively, the software may offer too many options, and you're accidentally applying color transformations in both the hardware and the software.
- Finally, if you can afford it, I highly recommend investing in color management software. Although it costs close to $300, MonacoEZcolor is probably the best all-around solution for most of you. The downside for me: Once you buy it, you'll probably lose all interest in this discussion.
Much as I'd love to write a detailed technical treatise on color theory, there are a gazillion people who've already thoroughly covered the subject. So if you have a yen to know--in exhaustive detail--why the colors on your display don't match those that emerge from the printer or TV, start by visiting the "Color management and color science: Introduction" section on the Norman Koren Photography page. In fact, the site is one of the best imaging technology references on the Web; if you frequently let your inner geek out for a stroll, bookmark his site now. For offline study, you can download the International Color Consortium's Why Color Management? PDF file. The organization is also responsible for digital color-matching standards.
Lesson 1: The ABCs of RGB
Just as all words are constructed of combinations of letters, all colors are constructed of combinations of primaries: the basic color attributes, which, in various mixes, produce all hues. The primaries can be colors we inherently understand, such as red, green, and blue. They can be visual attributes, such as hue, saturation, and lightness. Or they can be more abstract and difficult to visualize, such as L, a, and b or Y, Cr, Cb. Mathematics and physiology dictate that it takes exactly three primaries to define a unique set of colors; we only add extras, such as combining K with CMY, to compensate for real-world output limitations. If you think of the three primaries as coordinates on a 3D graph, then all the possible combinations of primaries form a 3D volume, or a color space.
Since each color space is formed by a different set of primaries with different characteristics, each 3D volume has a different shape--in other words, it produces a different set of colors. All color spaces overlap in various places, and all are a subset of the biggest color space: that defined by the human visual system. Color, by definition, is the reaction of organs in the human eye to certain frequencies of light. So if we can't see a color, it doesn't exist.
Because of the physical limitations of devices such as monitors and printers, each can produce only a subset of colors within the color space it operates. We refer to that subset as the device's gamut. So to match colors across devices, you not only have to deal with the fact that they produce different sets of shades, but that they can't always produce the broadest set of colors possible. Color management is the way we convert colors from space to space across devices.
Next lesson: Same primaries, different spaces, or Why I hate sRGB.