What does it mean, to copy a lens profile correction from one photo to another in lightroom?

Question

As the title says, what happens when copying a "lens profile correction" setting from one photo to another in lightroom?

Supposing I have two photos, one shot at 10mm, one shot at 20mm, both using the Sigma 10-20mm lens. If I apply the lens profile correction in lightroom (to correct for vignetting and distortion) to the 10mm photo, then "copy settings" from this photo and "paste settings" on the photo shot at 20mm, will this apply the correction for 10mm to the 20mm photo? Or is it more like a boolean yes/no as to whether to apply the appropriate profile corrections to the receipient photo (Eg: I check the box in Lightroom on a 10mm shot, copy settings and paste onto another shot taken with an entirely different lens, will copy/pasting of settings apply the different lens's profile to the new photo?)

Answer 1

In Lightroom there are various settings that come under the 'Lens correction' umbrella. The 'Enable Profile Corrections' flag will correct the image based on the type of lens it was taken with, so if you copy it from an image taken with a 10mm lens onto an image taken with a 20mm lens, it will correct the latter for distortions caused by the 20mm lens.

If however you make manual adjustments to the 10mm lens's distortion and copy them across, then the adjustments themselves will be copied, meaning the changes to the 20mm image will not necessarily counter the lens's built-in distortion.

This all assumes that the lens itself has a profile that Lightroom recognises. Some older lenses may never be supported, and some brand new ones may not be supported unless you have the very latest updates applied.

Answer 2

When you copy your lens profile settings and paste them on another picture taken with the same lens you will have the same correction applied. In case of a different lens you will have the same parameters applied on a different lens profile.