[argyllcms] Re: Colprof feature request: amount of black point hue correction control

Gerhard Fuernkranz wrote:
> I think to remember that quite some time in the past I had encountered
> an issue where obviously an ink limit of 290% prevented the B2A tables
> from outputting low RGB numbers close to [0,0,0]. Supplying the option
> -l300 to profile and icclink solved the problem. I still don't know why
> an ink limit was used for RGB at all (does this make sense?), and why
> profile was assuming an ink limit of just 290%, when no explicit -l
> option was specified on the command line. I don't know, whether this is
> still a potential issue with recent 1.0 versions.
>   

I digged out some of my old .ti3 files, and yes, this still seems to be
an issue with version 1.0.3.

$ colprof -v -B xxx
Total ink limit being used is 290%     <=====
No black ink limit being used
No of test patches = 750
Estimating white point
[...]

I'm also wondering how the ink limit is propagated to collink? Even if I
create the device profile with "colprof -l300 ...", a subseqent collink
(using this device profile as destination) still produces a too bright
black unless I explicitly supply -l300 to collink as well.

Regards,
Gerhard

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