Adam McKenty <[EMAIL PROTECTED]> wrote: >Thanks for the useful info David. > >They're being printed commercially (but not on a press) and when I asked >the fellow at the printer he said, with some hesitation, that the images >should be in CMYK. If an RGB workflow is standard as you suggest, >however, the eventual conversion must not be too damaging to the >appearance of the image, so (if my screen understood these things) I >should be OK doing the adjustments in RGB. > >Thanks for your help,
A couple of points: If you are actually *paying* for this printing work, I think you need to find out a little more about they're doing it. "I'd guess some form of colour laser printer" certainly wouldn't cut it if it were *my* money! I'd want to know *exactly* what's going on. Is this the Kodak/Heidelberg "Nexpress" system or something like it? Secondly, if they think you can do a better job of converting from RGB to CMYK than they can, I'd be concerned. Thirdly, there are a lot of specific CMYK profiles that you can use in Photoshop (I think the default is U.S. web coated SWOP 2). Ask them which one they recommend (and why). Their willingness/ability to answer this question can reveal a lot. Martin Evening's "Photoshop for Photographers" covers all this in some detail, though not as much as something devoted specifically to prepress preparation. You'll want to turn on Photoshop's "Gamut Warning" to see what colors in your images fall outside the CMYK color space. The book suggests ways of pulling them back into gamut without damaging the image too much. The author also mentions that there are a lot of print shops, even ones that have been in business for a long time and that produce excellent output, that don't have a real handle on color management: They simply have, through trial and error over the years, got all *their* scanners/printers/monitors working in harmony with each other, so that their inaccuracies cancel each other out. This kind of "in-house-only color management" is more common that you'd think. I'd suggest you make sure your own monitor is accurately calibrated, get your images looking the way you want them (use that out-of-gamut warning) and have this printing company make a single test print for you. If a significant print run or a significant amount of money is at stake, I'd make it a shot of a color chart of known values rather than an ordinary photo. Perhaps this company can show you some samples of their work (both the final prints *and* the files they came from, so you can compare). You might also ask if you can view your images on one of *their* calibrated monitors. -- Mark Roberts Photography and writing www.robertstech.com
