Feature request: lens AC correction

Software RawTherapee
#1

I’ve a problem with AC correction with lensfun with my camera.
My canon has in exif these tags:
FocusDistanceUpper
FocusDistanceLower
and it hasn’t “Subject Distance” which i think it’s needed for using AC remove with lensfun.
In fact i can’t use this feature with my camera.
Can the mean of FocusDistanceUpper and FocusDistanceLower will be read as subjectdistance and so it enables AC correction feature?
IMHO I would suggest to correct AC for infinity focus if the subjectdistance isn’t founded or the lens is used in manual. The best, but more complex, is to add a box where the user can add the distance.
I want to thanks all of you that works for this beautiful program

Thank you.

#2

Are you talking about chromatic aberration? CA?
Foy Bayer Cameras RT has very good automatic CA removal in the RAW tab. And I never before heard about Subject Distance being an important parameter, only the lens itself and what aperture was used.

#3

Hi Sunhillow. Yes I’m talking about Chromatic Aberration.
Rawpedia says fol lcp: “Chromatic aberration correction is only supported if the Exif information contains the focus distance (e.g. in DNGs from Nikon files).”
Thanks for the tip but I’ve tried CA in the Raw tab but it looses too much color (even if I use “Avoid color shift”). I’ve tried a lot also in astrophotographs…

#4

If your lens isn’t supported in lensfun you can calibrate the lens yourself, or contribute calibration photos to the project’s calibration service here.

#5

Thanks Karl for the reply but it seems that the lens i’ve used is supported (Canon 70-200 L IS). I’ve to try with a different camera with different exif…

#6

I’m stupid…i haven’t seen that my lens has the TCA only for cropped camera…
thanks very much Karl

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