DEC colours

John> Why I like RGB, chapter 3... All of electronic graphics is John> based on it. If it looks good on a TV, a computer monitor or John> anything from a Digicam, then it has been RGB digitized at some John> point. A digital camera just seems like a super convenient John> instantaneous color digitizer. You don't mix pigments from Red John> Green and Blue but the result of any pigment mix color can be John> communicated with RGB very well. No, it can't. There are colors that can be expressed in CMYK (four color "process" printing) that cannot be expressed in RGB. There are colors that can be made up in pigments that cannot be expressed in either. People who do this stuff for a living talk of "gamut" -- the range of colors that a particular system can describe. The RGB gamut and the CMYK gamut largely overlap, but each has a range outside that of the other. And there are other schemes (like Lab) that have yet a different gamut. For that matter, there are printer with more than four colors -- that is done to get a larger gamut. You can read about this stuff in the Adobe Photoshop manual, or in Electronic Publishing magazine, or in any decent textbook on color printing. If you want to do professional grade color, you have to go way beyond the narrow confines of thinking about color as simply RGB color. paul