[argyllcms] Re: lightness adaptation algorithms
- From: Rolf Gierling <mail@xxxxxxxxxxxxxxxxxxxx>
- To: argyllcms@xxxxxxxxxxxxx
- Date: Thu, 8 Sep 2005 19:29:56 +0200
Hi Roberto,
I
know, "change your proofer", but no, the problem is the source which
is the ubiquotuos (here) Matchprint.
Not the proofer, but the paper would help.
Question is, what's the best curve/formula/algorithm do to it? because
linear scaling doesn't sound as the best. Maybe scaling with some
perceptually linear gamma (L* is not perceptually linear, right?); or
maybe in shadows we need to scale a* and b* too, to preserve the
original chroma slope on the gamut edge. Maybe a scaling function that
gets applied only on the ends but merges smoothly into the rest of the
range. Or whatever. Suggestions?
Linear scaling is, from what I know, the best.
I made research in this in my examination, and I
have never seen any other document that say
something else.
Also, in your special case, if you are really mapping
from 95/5 to 93/7, the midtone will exactly remain 50.
Somebody correct me if I'm wrong
Rolf
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Dipl.-Ing. Rolf Gierling
Colormanagement
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Germany
Tel. +49 (0) 2 41 / 4 01 25 79
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Author of "Farbmanagement"
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ISBN 3-8266-1382-1
- References:
- [argyllcms] lightness adaptation algorithms
- From: Roberto Michelena
Other related posts:
- » [argyllcms] lightness adaptation algorithms
- » [argyllcms] Re: lightness adaptation algorithms
- » [argyllcms] Re: lightness adaptation algorithms
- » [argyllcms] Re: lightness adaptation algorithms
- » [argyllcms] Re: lightness adaptation algorithms
I know, "change your proofer", but no, the problem is the source which is the ubiquotuos (here) Matchprint.
Not the proofer, but the paper would help.
Question is, what's the best curve/formula/algorithm do to it? because linear scaling doesn't sound as the best. Maybe scaling with some perceptually linear gamma (L* is not perceptually linear, right?); or maybe in shadows we need to scale a* and b* too, to preserve the original chroma slope on the gamut edge. Maybe a scaling function that gets applied only on the ends but merges smoothly into the rest of the range. Or whatever. Suggestions?
Linear scaling is, from what I know, the best. I made research in this in my examination, and I have never seen any other document that say something else.
- [argyllcms] lightness adaptation algorithms
- From: Roberto Michelena