[argyllcms] Re: Clipped shadows (bad gamut mapping?)

  • From: Andrew Lutomirski <luto@xxxxxxx>
  • To: argyllcms@xxxxxxxxxxxxx
  • Date: Sat, 3 Oct 2009 19:58:43 -0400

On Sat, Oct 3, 2009 at 7:21 PM, Andrew Lutomirski <luto@xxxxxxx> wrote:
> I'm profiling my laptop display, which can't display very dark blacks.
>  I mainly want to use the resulting profile to display sRGB images
> using the perceptual table, and I'd like it to map nicely between the
> sRGB gamut (which, IIRC, contains black) to my display's gamut (which
> doesn't contain black).
> All of the LUT-based profiles I get from colprof, though, clip shadows
> badly, as shown by xicclu -g -fb -ip, by lcms's icctrans (unless I
> request black point compensation), and by looking at images that have
> detail in the shadows.  (In fact, the profile isn't even always
> monotonic for inputs below 30 or so, which seems strange.)

It looks like the problem is that the v2 sRGB profiles here:


both have funny gamuts that don't include black, so colprof is
behaving reasonably.  If I use AdobeRGB, I get great results.  Does
anyone know where to get a "correct" sRGB profile nowadays?

Ideally, argyllcms would bundle an sRGB profile or .gam file for
exactly this use, since it seems silly for people with crappy laptop
displays to aim for anything better than sRGB.


Other related posts: