At its core Krita is, like GIMP, a FOSS raster graphics editor, but the emphasis does lie on digital painting (and 2d animations). This doesn’t mean that it can’t handle images, on the contrary!
Although my experience is still limited at the moment I find it a very nice replacement for the stuff I did, and wanted to do, in GIMP. Especially its all-round non-destructiveness and ease of use, compared to GIMP, is what made me switch.
OK, what did I actually do with Krita in the above image (probably too much, but I’m still learning and need the practise ):
- Removed a white, dead Ivy branch sticking in from the border. Used the clone tool, sharpen brush and one of the paint brushes.
- Applied a gradient. Initially it was a very dark purple - mid green - ‘warmer’ white combo, but the green part didn’t work and was removed in the end (gradient became transparent for the mid tones). Changing the opacity of individual colours and adding/changing colours on the fly is very easy to do in Krita!
- Did some slight dodging and burning. I probably used a method that was a bit over the top for this image, I could have used the (destructive) dodge and burn brushes. But: Used 2 (black) paint layers that I converted to a dodge and a burn filter layer. These are non destructive and rather precise in what you want to target (you can set highlights, mid-tones or shadows and adjust the overall exposure). The specific dodging/burning can be done with a brush of your liking and reduced opacity and/or flow.
- I very slightly saturated and hue shifted the brown/gold parts of the bark by using the colour selection tool and converting the created selection into a cross channel adjustment curve (as a filter layer). This filter can do changes based on a certain input (lightness, saturation etc.) and target (HUE, lightness, RGBA, etc).
All of the above is non-destructive and relatively easy to do. Haven’t been able to do something similar in GIMP without having to go through all kinds of hoops and restrictions and still ending up with a destructive end-result.
EDIT: Added some detail to dodge/burn part.