Bug report - PL 5.2.0 : Panasonic S1R + Sigma 35mm 1:2 DG DN -> wrong lens identification

PL has officially no profile for the Sigma 35mm 1:2 DG DN (L-mount). When mounted on a Panasonic S1R, it is identified as Leica APO Summicron-SL 35mm and the wrong lens correction is applied.

I don’t know since when PL is doing this but back when I bought the lens, it showed as unidentified lens.

I can’t even delete the downloaded lens profile for the Leica APO Summicron since it is in use.

PL 5.2.0 - Windows.

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Good morning!

@TomWi could you, please, provide us with some sample images? Please, upload them via upload.dxo.com

and let us know when ready.

Thank you
Svetlana G.

That’s the case for quite some time and I already gave up hope it would be fixed any time soon. I don’t understand how DxO manages to confuse these rather different lenses, but why bother? I just use C1, no problems there with the manufacturer’s profile.

Done. 2 Images. Panasonic S1R + Sigma 35mm 1:2 DG DN (L-Mount)

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I went from C1 V12 to DXO and have no plans to go back.

Thank you! I’ve got the files. They’ve been sent to the dedicated team. @Marie , please, follow up.

Svetlana G.

I also did not plan to go back. Stuff like that

made a change of plan necessary. Good luck for you @TomWi :grinning:


we will plan the Sigma lenses for L-mount but I can’t provide a date of support yet.


Excuse me but this is not a request for lens support. This is a bug report about a lens (that PL does not support) that is falsely identified as a lens that PL supports.

Post deleted, should have read better…


To match an image and a module we use several Exif/MakerNote information in following order:

  • LensName
  • LensID
  • LensInfo (for example : 18-35mm F3.5-5.6)
  • Current information of focal and aperture

Information 1 and 2 are not always available (especially for cameras of old generation).
Any of this information could fit several lenses (1 and 2 are supposed to be unique but all makers don’t respect that).

So when a module for a couple doesn’t exist yet PhotoLab can propose a module for one or several other lenses.


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Aha, and you want me to believe, the Leica APO-Summicron-SL 35mm F2 ASPH ist about the same as the Sigma 35mm F2 DG DN | Contemporary? At 7.5× the price of the Sigma?

Sorry @Marie this is not even remotely believable. There needs to be another reason to confuse two extremely different lenses.

You seem to be questioning DxO’s motives or competence. Are you really suggesting they may be trying to make you believe that those two lenses are about the same or that they are somehow confusing these lenses when offering what you consider an inappropriate alternative profile? I assume it was probably just an attempt at sarcasm.

PhotoLab often suggests one or more alternative profiles for lenses when a specific lens profile is not available. The difference in the cost of a lens is an irrelevant part of that process. It’s about applying lens distortion corrections, vignetting corrections, sharpening, and chromatic aberration corrections.

While I don’t claim to know the exact process in which specific alternative lens profiles are suggested, it may just be based on available alternative profiles with the same focal length/range and f/stop range. Offering alternative lens profiles in PhotoLab is certainly not uncommon and in no way suggests that DxO considers the actual lenses equivalent to one another.

One can choose to use, or not use, alternative suggested profiles. They could be used as an alternative to manually adjusting an unsupported lens’ characteristics from scratch but whether that is advisable, I cannot say.


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