[scribus] Ink Coverage Preview differs from Acrobat Pro

[john Culleton]

On Thu, 7 Mar 2013 23:32:43 -0500
Jonathan Kreider <jonathan.kreider at gmail.com> wrote:

> On Thu, Mar 7, 2013 at 1:38 PM, john Culleton <John at wexfordpress.com>
> wrote:
> 
> > On Thu, 07 Mar 2013 06:35:11 +0100
> > "Christoph Schäfer" <christoph-schaefer at gmx.de> wrote:
> >
> > > Hi Jonathan,
> > >
>> >
> >  use a variant of a common icc profile to make sure that the
> > requirement of LSI (no more than 240% coverage) is observed.
> > Here it is:
> > http://wexfordpress.net/SWOPcoated5_240.icc
> >
> >
> >
> >
> >
> > --
>> >
> 
> Does this mean that if I use the same profile in Scribus and in
> Acrobat that I should get similar results?
> 
> @Christoph - > What are the variables that you are talking about?  I
> understand that there is a whole chain of processing that gets done
> during the printing process, but that is completely invisible to me.
> Is there a web site that has a tutorial on this that describes the
> process?
> 
> What I'm trying to achieve is sending a pdf for a circular (flier) to
> a commecial printer and have the confidence that the printed results
> will match my intentions.  This printing company has a "Prinergy"
> setup that does Gray Component Replacement, Sets total ink coverage
> to 280%, Black Start @30%, Black Max @90% and Black Strength @ 50%.
> At least that's what the printer people told me.  I understand this
> only in a general sort of way, but not really in terms of how it will
> affect the final product (which is printed, but I've not seen a hard
> copy of).
> 

Printers for the most part still use CMYK ink fountains or
cartridges, and cameras and monitors use RGB. The gamut or range
of colors available is wider in RGB than in CMYK. 
SWOP and my variant thereof yield CMYK values. But even in the
world of CMYK some printers (LSI is one) have set up stricter
limits on the amount of ink spread in "rich black" portions of
your document. So if you use "my" profile (provided by a kind
person on the icc profile mailing list) the output will be in
CMYK and it will not bounce from LSI for too much ink coverage.

Getting a proof copy is the only way to estimate what your cover
etc. will look like, and maybe not then if they use a different
press for proofs than for production. 

The good news is that if you go from RGB (e.g., a photo) to CMYK
printed (PDF) output and then go back to RGB in Adobe Reader no colors
or shades will be added. So the approximation will be close.   

It is also possible to just leave your file in RGB and let the
printer translate to CMYK. He knows his press better than you do.
In this case a proof is mandatory. I would err toward extra rich
colors in that instance.

-- 
John Culleton
Wexford Press
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