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QTR-Quadtone RIP

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RE: [QuadtoneRIP] Re: QImage, ICC Profiles, and some surprising results (long)

2006-09-04 by Terry Ritz

Roy (or anyone else), can anything be done to develop a profile that better
handles shadows (using QTR-CreateICC or another tool)? 

I've just noticed the same issue on a photo of a dark suit. The suit is well
defined on my calibrated monitor but is almost all black when printed using
a properly defined curve and a profile made using QTR-CreateICC. I converted
the file to this profile using Photoshop and perceptual intent.

I can understand why jkohn_home would fall back to using gray-lab / gamma+4,
but it seems to me that correcting the profile somehow, would be the best
solution. (BTW, thanks for posting your test results!)

Thanks,

Terry.

jkohn_home wrote:
> > So I did one final test using gray- lab instead of the 
> > profile, but boosting the gamma setting in QTR to +4 in 
> order to  darken the midtones some.
> > This proved to  be "just right", as the real-world image now showed 
> > excellent shadow  detail and the midtone values were closer 
> to where 
> > they should be:
> > 
> > http://www.pbase.com/image/66139883
> > <http://www.pbase.com/image/66139883>
> > 
> > So in the case of my HPR curves for the 2400, it looks like 
> I'm going 
> > to be printing directly from gray-lab using gamma=+4, 
> unless the image 
> > has no shadows to be concerned with (which is rare for me). The 
> > resulting  prints look amazing, it was definitely worth all 
> the work

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