Lens does not have the correct LensType number

[Marc-AntoineGelinas]

Hello,

I have an issue where I use 2 Sigma lenses, Sigma 150-600 DG OS HSM | C and the Sigma 70-200 DG OS HSM | S

The issue is that the 150-600 gives the wrong LensType through Exiv2 :

$ exiv2 --print t --grep lens/i IMG_0434.CR3

Exif.Photo.LensSpecification   Rational    4  150-600mm

Exif.Photo.LensModel      Ascii      46  150-600mm F5-6.3 DG OS HSM | Contemporary 015

Exif.Photo.LensSerialNumber       Ascii      11  0000000000

Exif.CanonCs.LensType     Short    1  Unknown Lens (624)

Exif.CanonCs.Lens  Short   3  150.0 - 600.0 mm

Exif.CanonFi.RFLensType   SShort      1  n/a

Exif.Canon.LensModel     Ascii  138  150-600mm F5-6.3 DG OS HSM | Contemporary 015

{Manually shortened}

The LensType should be 183, not 624, which is the id of the 70-200. The lens seems to be unproperly recognized and defaults to 624. The 70-200 gets recognized properly as 624, which somewhat prevents me from setting the lens manually in the .exiv2 config file since both lens would now be recognized as the 150-600 since they're both from the same manufacturer.

Is there anything I could do to manage this in one way or another? I've searched this repo's issues as well as Darktable's, but coudn't find someone having the same issue. I am well aware that Lens ID is a complicated issue, so I am prepared for the answer to simply be "No".

For more context, I have been using there two lenses on two different Canon RF bodies through the official Canon ef-rf basic adapter.

Thank you very much.

[clanmills]

624 is the data in your file. Exiv2 reports what is present. If that's incorrect, you'll have to report it to Canon as they wrote that data.

You might be able to fix this using the configuration file ~/.exiv2

[canon]
624=Sigma 70-200 DG OS HSM | S
183=Sigma 150-600 DG OS HSM | C

[Marc-AntoineGelinas]

Thank you for taking the time to answer Mr. Mills.
I figured Canon was partially to blame for that issue. I'm not exactly surprised since they aren't too keen on 3rd party lenses and in this case it's even from a different mount with an adapter.

I did try to add the lines to my ~/.exiv2 file, but as expected, the 150-600 files simply get recognized as 70-200, which causes an entire other problem.

I'll live with it until I change one of these lenses.

Thanks again and I wish you a very good day.

[clanmills]

@Marc-AntoineGelinas

The test I would perform to confirm that Canon have not stored the appropriate metadata for your Sigma lens is this:

534 rmills@rmillsm4:~/Desktop/Harry $ exiv2 -Pvk -g lens/i ~/Stonehenge.jpg 
Exif.Nikon3.LensType                          14
Exif.Nikon3.Lens                              180/10 2500/10 35/10 63/10
Exif.Nikon3.LensFStops                        55 1 12 0
Exif.NikonLd3.LensIDNumber                    146
Exif.NikonLd3.LensFStops                      55
535 rmills@rmillsm4:~/Desktop/Harry $ 

This shows the "raw" lens data. If there is no significant difference between your two Sigma lenses, then our diagnosis is correct and you mark this discussion as "Answered"?

[Marc-AntoineGelinas]

$ exiv2 -Pvk -g lens/i IMG_0526.CR3
Exif.Photo.LensSpecification                  150/1 600/1 0/1 0/1
Exif.Photo.LensModel                          150-600mm F5-6.3 DG OS HSM | Contemporary 015
Exif.Photo.LensSerialNumber                   0000000000
Exif.CanonCs.LensType                         624
Exif.CanonCs.Lens                             600 150 1
Exif.CanonFi.RFLensType                       0
Exif.Canon.LensModel                          150-600mm F5-6.3 DG OS HSM | Contemporary 015
Exif.CanonLiOp.DigitalLensOptimizer           0
Exif.CanonLe.LensSerialNumber                 0 0 0 0 0
Exif.CanonAfC.USMLensElectronicMF             2
Exif.CanonAfC.LensDriveWhenAFImpossible       0

$ exiv2 -Pvk -g lens/i IMG_3181.CR3
Exif.Photo.LensSpecification                  70/1 200/1 0/1 0/1
Exif.Photo.LensModel                          70-200mm F2.8 DG OS HSM | Sports 018
Exif.Photo.LensSerialNumber                   0000000000
Exif.CanonCs.LensType                         624
Exif.CanonCs.Lens                             200 70 1
Exif.CanonFi.RFLensType                       0
Exif.Canon.LensModel                          70-200mm F2.8 DG OS HSM | Sports 018
Exif.CanonLiOp.DigitalLensOptimizer           0
Exif.CanonLe.LensSerialNumber                 0 0 0 0 0
Exif.CanonAfC.USMLensElectronicMF             2
Exif.CanonAfC.LensDriveWhenAFImpossible       0

Going with the raw lens data, yes the lens type is the exact same between the two lenses. I'll mark this as resolved since it's not a problem with exiv2, but with Canon.