Chromatic Aberrations does not remove all distortions
The CA module is able to remove most but not all chromatic aberrations. Depending on the particular image or surrounding pixels, distortions may remain in the image.
Notice that while the photographer's jacket is free of distortions, there is still a magenta line along his hood.
To compare I have examples of the same RAW-file processed in Lightroom with and without CA-correction enabled.From DT, only exposure adjusted:
#2 Updated by François Guerraz over 5 years ago
DT is usually good at removing CA, but it seems to have a problem with some lenses like those that have apochromatic elements. Which is sort of understandable because they probably have non-standard kind of CA, but which is annoying because we end-up, post-processing, with images with more CA left!
It's particularly conspicuous with a Sigma 300mm F/2.8 APO.
An improvement would be greatly appreciated or at least, would it be possible to have a "manual control"?
I don't know how the automatic CA correction works, but I suppose it has a look at a sample in the corner of the images (where the CA should be more pronounced) to determine what are the CA coefficients. I noticed that images with little contrast in the overall image (like a picture with a lot of snow and sky), DT does a very bad job at correcting the CA.