Sun

[shold]

Hi,
i need a suggestion for my high resolution sun image.its a gray Image.   
I would like to increase the contrast for the granulation, but not for Umbra/ Penumbra.
the mask tool is active, but only for RGB. Is there a way, a mask for a gray image to make?

regards
Siegfried

[Carlos Milovic]

It doesn't matter if the image is grayscale or color, the mask system works just the same. You only have to use another grayscale image as the mask.

So, if you want to increase the contrast of the granulations, you may try ATrousWavelets, to perform local contrast enhancements, instead of a global one throught Curves.