[texhax] CMYK color v. RGB

[Steve Schwartz]

I'm not a colour expert at all, but have hit a couple of things in the
past, one of which is that some ghostscript-based scripts (such as
ps2pdf or epstopdf) set options that are not always optimal, such as

-dPDFSETTINGS=/prepress  (which epstopdf uses instead of /default
or /printer)

Also, if you read the Ps2pdf.htm documentation (it should live in the
same directory as the ghostscript Use.htm documentation) you will see
that there are a number of colour-related options you can pass to ps2pdf
to control RGB vs CMYK, and probably things like colour depth which may
well affect the result. Maybe this will help.

Steve

On Fri, 2008-12-19 at 14:03 +0100, Lars Madsen wrote:
> Niall Mansfield wrote:
> > We've just had a book printed, and there are a few color problems:
> > more or less consistently, some blues come out looking a little
> > too green, and others look purple.  The printing company say this is probably due to
> > the RGB -> CMYK color conversion, and say that we should
> > ensure images are in CMYK format rather than RGB before
> > they are embedded in the PDF.
> > 
> > We're using LaTeX, Xfig, GNUplot, Metapost, and all the usual
> > tools on Linux.  We produce the book as PostScript, and then
> > ps2pdf that, to send to the printers.
> > 
> > I don't think it's possible for us to use CMYK.  Is it?
> > Does anyone else have experience of similar problems?
> > 
> > 	Thanks,
> > 	Niall
> > 
> > ps: we had advance review copies printed digitally.  They were
> >      fine; only the litho copies were weird.  The printers say
> >      it wasn't a problem with their inking of the litho machine,
> >      and insofar as I understand what they are talking about, I
> >      believe them.
> 
> have you had a look at xcolor? Though you might want to use pdflatex 
> directly, not sure if postscript actually support cmyk.
> 
> 
> 
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