Vignetting correction / highlight recovery in ART / Rawtherapee

Just an observation that had me puzzled for a while in ART.
When the ‘vignetting correction’ box is ticked under lens corrections, (not surprisingly) it brightens the outer portions of the images. However this seems to result in highlights being brightened so that they can no longer be recovered by any means.

I guess the simple answer is don’t tick the vignetting box if you want to recover highlights but I am just pointing it out, because it had me stumped as to why I sometimes couldn’t recover highlights.

Not sure about darktable, as the vignetting correction doesn’t seem to do anything. In RawTherapee, you can’t tick the vignetting correction box for my camera. Perhaps it is just an issue with the lensfun profile for my camera?

Here is the raw file as an example, not a great photo, but illustrates the point.
Coombe Abbry Walk 7.RW2 (14.7 MB)
This file is licensed Creative Commons, By-Attribution, Share-Alike

It definitely is present in darktable as well. Brightness jumps significantly when turning on lens correction (even if only limited to vignetting). This does influence the pipeline as well.

Have a look at the values in the color picker module.

Vignette off:

Vignette on:

You mention recover highlights, but about 80% of your sky is blown out (70% or so all 3 channels). I’m not so sure it is reasonable to expect wonders in this case. You can’t reconstruct what isn’t there, you can only inpaint/cover it up.

RawTherapee 5.8 has the same “issue”. Not sure which version you are using but the latest stable does recognize your DMC-LX100 + Leica lens. I should know, I have the LX100 II :smile:

I’m not sure about ART, but RawTherapee has the Vignetting Correction option (two below Profiled Lens Correction). Try playing with those settings instead of the automated one.

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My take: because your highlights are blown-out to start with! Hard to recover details, even with the other tools in ART (vignetting correction [the one in the Special effects section], Dynamic range compression, Tone equalizer, Tone curves…).

Edit: @Jade_NL types faster than me.

Hi I, realise the photo has lots of blown out highlights, much of it beyond repair.
Just pointing out that the auto lens profiled vignetting correction can make things worse, if like me, you just turn on the lens corrections and forget about them…


no, it’s a side effect of how vignetting correction works in ART (and RT). Profiled vignette correction is applied on the raw data, and sometimes it might push some values beyond the white point. The same can happen with flat-field correction, for which there is a “clip control” slider to try to mitigate this. I guess something similar could be done also for the vignetting correction, but I’m not sure if it’s worth it (as written in the clip control tooltip for flat-field, applying the mitigation can sometimes cause artifacts). If you see that happening, it’s probably wise to disable automatic vignetting correction and do the correction later with other tools (e.g. the manual vignetting correction tool in the transform tab).


Thanks really helpful. Good to know about the side effect and how to avoid it…