Am Dienstag, 24. Juni 2008 20:02:32 schrieb Craig Ringer: > Andrew A. Gill wrote: > > If you intend to print something out, always use CMYK. > > This is not necessarily always the best choice: > > - Many home printers expect RGB input and will do a very poor job when > fed pre-converted CMYK data. You're better off using an RGB colour > profile to transform colours for these printers, then let their > drivers do the CMYK, CcMmYK, etc translation. This is especially > important for "photo printers" and other six-or-more colour printers, > as most CMYK spaces cannot represent their full gamut, where a > wide-gamut RGB space like Adobe RGB is well suited to it. > > - Modern print shops may accept PDF/X-3 with ICC-tagged RGB data. This > lets you send your data to the print shop in their original colour > spaces and lets their RIP do the conversion with its often superior > knowledge of the performance of the press. Unfortunately, many > print shops will just look at you funny and say "why do you want to > send RGB?" because they just don't get ICC colour workflows, but > a few are starting to get it. It doesn't help that ICC workflows are > hard to get right and somewhat easy to misunderstand. > > For most print shops, though, I agree that sticking to pre-converted > CMYK is currently the way to go. > > -- > Craig Ringer Thank you for your advice. So, if I would want to convert an image to cmyk, what would I use - Cinepaint, Krita, Gimp?
Martin > > Whatever > > > software you are using will have to convert to CMYK anyways, > > because that is what the separations will have to be, and those > > are the colors of the inks that the printer/press will use, so > > starting CMYK can only help. The advice for work that is > > displayed on a computer screen is to stick to RGB, since that is > > what screens use, but there are benefits to having that be CMYK, > > as well (for me, the addition of the K channel sort of acts as a > > separate value channel, which can be useful for brightening an > > image without introducing color shifts--I would love to see > > RGBW as a proposed standard). > > > > There's also the possibility that it will mask some errors that > > won't be visible until press time. For example, I went into GIMP > > and created a red image (255R/0G/0B), imported it into Scribus > > and created a red box. Both are similar colors, and you might > > not notice any discrepancy until you get the plates back from the > > printer and for some reason, you've got both colors scaled back > > to a 90% linescreen, causing that nice, clean edge on the font to > > become ragged. > > > > So CMYK for print work. RGB for screen work. But above all > > else, if ot's possible, do not mix. > > _______________________________________________ > scribus mailing list > scribus at lists.scribus.info > http://lists.scribus.info/mailman/listinfo/scribus
