At 08:09 08/08/2003, Darrian Young wrote:
From this
viewpoint, in a sense it does not really matter which kind of
colorspaces are in
PDFX3 - we only have to take care of the right
choice in correct rendering to the output
intent.
This sounds too easy to be possible, but in fact
today's workflow-tools
are sophisticated enough to allow this on a high
professional level.
Are you saying that you are using some application that makes on-the-fly
decisions about whether to use a RelCol or Perceptual trasnfomation
depending on the image? If you don't mind divulging secrets, I would be
very interested to know.
This kind of on-the-fly decision would mean that you are not making PDF/X-3
compliant output. One of the main points of the PDF/X standards is to
ensure maximum similarity between output of the same file on different
sites, using different equipment. You can only do that by making the same
decisions about rendering intent at every site, and the way the standard
requires you to do that is to use the intent selected in the file (or using
the PDF default).
PDFX3 gives us
all options - completely CMYK or completely RGB or
completely mixed, preferably
device independent. No reason to be scared.
I definitely agree - we currently set up CMYK PDF/X-3 workflows and it
works very well.
Despite many discussions with lots of people I still don't really
understand the value of a CMYK-only PDF/X-3 workflow. If you want CMYK only
isn't it easier to ask for PDF/X-1a? That's simpler to describe and simpler
to configure the tools for.
The only half-way sensible reason for CMYK-only PDF/X-3 that I've heard is
that people want to use device independent colour spaces for the alternate
colour space of spot colours - the idea being that they're likely to get
proofed more accurately on a CMYK proofer. I still have serious concerns
about this workflow because there's nothing to stop a designer creating a
file with 'spot' colours that should be converted to CMYK for the press.
Then you have device independent objects in something that's nominally
CMYK-only, and sooner or later you'll get bitten by colours that are
supposed to be identical in different objects not matching on the final print.
Avoiding that issue just makes the description of how a designer should
make a good file more difficult again.
Regards
Martin Bailey
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Senior Technical Consultant +44 1223 873800
Global Graphics Software
http://www.globalgraphics.com
Developers of Harlequin, Jaws, Jaws PDF & MaxWorkFlow
martin.bailey(a)globalgraphics.com
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If my views didn't usually coincide with those of my employer
I wouldn't want to work here, but I am not a spokesman for
Global Graphics Software
and the buck stops with me for what I say.
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