Is this lens supported by lenslensfun? You can correct CA from lensfun as well.
1 Like
I don’t know what can be done with darktable, but as a user of cheap lenses I’ve had to develop a system to remove chromatic aberrations, mainly by the (unorthodox) use of the defringe tool.
This is what I could get from your latest playraw:
P9120141.jpg.out.pp3 (13.4 KB)
I must say that a perfect image from your raw is quite unlikely, TBH: there are big aberrations that will lead to gray borders unless you take a lot of care with them. In this crop I have:
- used CA with just one iteration: mainly because it seems to be enough, but also to compare results with darktable. If you use 2 iterations (default) the image may be better in certain areas, but the gray borders are wider
- even though I have lowered the exposure, I also have left it at a point where the highlights are burned (clipped). This way it helps to hide a bit those gray borders
- the most part of the trick is how I use the defringe tool: look carefully and you will notice that all the color points are raised at least one pixel or so. This assists to remove lots of artifacts here and there (not only on the highlights). Look on the highlights on the stones, the grass, or the streaks of water while turning the tool on and off. Look also on the trunk of the rightmost part of the image. Of course this leads to some loss of color in the image, but I usually choose a midpoint where the colors look natural (or at least believable). The trickiest point here comes after you have removed the undesired fringes. Then you have to carefully choose the appropriate radius (I almost always leave the Threshold at 0). Too much and you will introduce gray borders. Too low and not all fringes will be removed.
Of course the best solution would be a better lens 
Hope it helps
4 Likes
how?
edit: ok, I just checked, that’s obviously the lens correction module.