You might want to try putting 'gimp cmyk' into Google and have a read
On Sat, 14 Jan 2006, Carlos Muncharaz wrote:
> Hi, I have just added to the mail list and here I bring some questions:
> What about Gimp support for CMYK color mode? Have you discuss about it?
> Will Gimp handle CMYK images? Can a graphic designer who works with CMYK
> images to send to printer work with Linux and Gimp?
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