Color Spaces & Printer Profiles Revealed
Crayon color choices have some important similarities to how color spaces are defined and used
If you create images for web publications or other media that will be displayed primarily on a computer monitor (slideshows, screensavers, etc.), you're better off using sRGB. Typical computer monitors can't display some of the colors that are found in Adobe RGB, but they can display all sRGB colors. By the same token, if you plan to send your images to one of the generic online printing services, shoot in sRGB—or better still, shoot in Adobe RGB and convert them to sRGB before you upload them. sRGB is the color space that online printers are expecting. If you submit Adobe RGB images to an online lab, the prints may appear washed out because some of the intermediate colors are "missing" and have been "replaced" with colors that the printer can't reproduce.
Calibrating your color monitor will make your colors more consistent and make it easier to get a good print. Calibration is much easier than it sounds. Yes, it's possible to process color images without going through this procedure, but unless your display is calibrated, you're literally guessing at what the final outcome will be.
On the other hand, if you make inkjet prints on your desktop, or if you shoot for commercial publication, you can take advantage of the wider gamut and shoot in Adobe RGB. Many of today's multi-ink photo printers can produce all of the colors found in Adobe RGB-and more. In particular, colors that range toward cyan—certain blues and greens—are better represented in Adobe RGB color space. Potentially, nearly any image that contains sky, water or foliage will be more faithfully reproduced.
After editing in Adobe RGB (or sRGB, for that matter), you're ready to create great prints, right? Almost. Regardless of which color space setting you use when you capture your images, you can't control the appearance of the printed output unless your computer communicates the color information correctly to the printer. Fortunately, there's a standardized way to do so. ICC color profiles describe how a particular device reproduces color—it's essentially a map of the device's color space.