chromatic aberrations vs defringe

Hello,

In this image there is some visible chromatic aberration on top of the the tower.
The automatic correction works very well but leaves a bit of wrong color at the border to my eyes which does not bother me at all but I wanted to play a bit with the chromatic aberration correction and defringe modules.
To my opinion it is possible to correct the image with both modules.
My question is, are they somwehat redundant and should they not be in the same tab?

P7310931.ORF.arp (10.5 KB)

P7310931.ORF (14.7 MB)

Licensed under a Creative Commons Attribution-NonCommercial 4.0 International License

Thank You.

B. Roessli

To add a license just add the text “file licensed under xyz license”

I did it, thank you

Hi,

No, they are not redundant. The CA correction module targets lateral chromatic aberration, and does it by operating geometric transformations to the individual RGB channels. The defringe module targets more general kinds of color fringing (such as axial chromatic aberration) that cannot be easily corrected by geometric transformations of the image channels. It works by detecting colored edges and desaturating them, basically, so it is more prone to artifacts and unwanted side effects. In general, I’d say that you should prefer the CA correction modules if they work, and only use defringe to (try to) hide aberrations that cannot be fixed otherwise.

HTH

Thanks for the explanations!
Cheers,
B. Roessli