Re: [Gimp-developer] 'gimp-levels' procedure with GEGL activated.

> 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
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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.

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