Open source photo processing with Darktable: 
It’s hard to say how good photographs happen. You have to be in the right place at just the right moment. You have to have a camera at the ready and an eye for composition. And that’s just the part that happens in the camera. There’s a whole other stage to great photography that many people don’t think about. It used to happen with lights and chemicals in a darkroom, but with today’s digital tools, post-production happens in darkroom software.
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Supporting Open Source.
Have you tried: Farking?