> Date: Sun, 15 Jul 2012 13:37:27 -0400
> From: l elle stone gmail com > To: exposito ssp infomed sld cu > CC: gimp-developer-list gnome org > Subject: Re: [Gimp-developer] 'gimp-levels' procedure with GEGL activated. > > ...But Levels with "Colors, Use Gegl" checked affects the midtones more > than the shadows. The difference is noticeable with an sRGB image, > drastic with a linear gamma image. > > Elle > > -- > http://ninedegreesbelow.com > Articles and tutorials on open source digital imaging and photography > _______________________________________________ > gimp-developer-list mailing list > gimp-developer-list gnome org > https://mail.gnome.org/mailman/listinfo/gimp-developer-list Go to the Curves tool and adjust the white point down to 128. This should darken the image by 50% (eyedropper verifies that white is now 50% grey), however if you do the same with Colors > GEGL activated then your results are quite different - instead of coming out at 50% grey, the same white pixel now comes out at 22% dark grey - which is clearly incorrect behavior. But it's also conveniently about a 0.45 gamma correction from the correct value.... -- Stratadrake strata_ranger hotmail com -------------------- Numbers may not lie, but neither do they tell the whole truth. |