COMPUTERFREAKED

I am by far no expert on this but there are 2 different kinds of CA. LCA and TCA. TCA is independant of aperture and can be more or less corrected in software. Hence no aperture selection is needed for correction. LCA is aperture dependant but can not be corrected in software as far as i know. https://photographylife.com/what-is-chromatic-aberration/

Canon FDn 50mm 1.4 Vignetting lines

Attached the new corrections. Greetings ;)

Canon FDn 135mm F2.8 new lens data

OK i figured it out. Calibrate.py leaves a few files, probably to avoid recalculating. Since this is a lens without exiv data I have to do the vignetting file by file since otherwise I don't know which vignetting line is which apperture. Therefore I recalulcate a lot and didn't notice this in the beginning. I will perform the vignetting corrections again and will come back to you!

I have the feeling there is something odd about the vignetting corrections. For each different apperture calibrate.py comes up with the same corrections. This should not be the case correct?

It seems i made a small mistake, but I can not edit the original post. Long story short it is an easy fix. Run ldconfig after installing lensfun. Then build Darktable.

Yes they do. I have now manually cut the vignetting lines from the 30mm f/1.4 DC DN to the 30mm f/1.4 DC DN | C 016 and all works well. To be clear: I provided the vignetting lines for this lens. Mine identifies as 30mm f/1.4 DC DN | C 016. Hence the vignetting lines I provided were added to a different entry for the sigma 30mm dc dn. As far as I know there is only 1 version of this lens but thats just me...