Exiftool shows incorrect lenstype

[kiekerjan]

I have a Sony ILCA-68 camera and use it with a Sigma 17-70 F2.8-4 DC MACRO HSM Contemporary lens (not OS because that is not included on the Sony Alpha mount).
According to the lens type database (https://exiftool.org/TagNames/Sony.html#LensType) this lens should have lens id 50493. However, when I let exiftool print my lens information it returns LensType 128 and identifies the lens as the non-contemporary model.

Code Select Expand

$ exiftool -a -G1 -s DSC04862.ARW | grep -i lens
[ExifIFD]       LensInfo                        : 17-70mm f/2.8-4
[ExifIFD]       LensModel                       : DT 17-70mm F2.8-4
[Sony]          LensType                        : Tamron or Sigma Lens (128)
[Sony]          LensSpec                        : DT 17-70mm F2.8-4
[Sony]          LensFormat                      : APS-C
[Sony]          LensMount                       : A-mount
...
[Sony]          LensSpecFeatures                : DT
[Composite]     LensID                          : Sigma 17-70mm F2.8-4 DC Macro HSM

Code Select Expand

exiftool -G1 -s -n DSC04862.ARW | grep -i lens
[ExifIFD]       LensInfo                        : 17 70 2.8 4
[ExifIFD]       LensModel                       : DT 17-70mm F2.8-4
[Sony]          LensType                        : 128
[Sony]          LensSpec                        : 01 17 70 2.8 4 00
[Sony]          LensMount                       : 1
[Sony]          LensFormat                      : 1
[Sony]          LensSpecFeatures                : 01 00
[Composite]     LensID                          : 128

There is an older model of the same lens that indeed has the LensType 128, but it is not the contemporary model.

Am I looking at this the wrong way? Is there something wrong in exiftool? Is my lens or camera wrong or lying? How do I get exiftool to identify my lens correctly?

[StarGeek]

This will probably require attention from Phil, who is currently on vacation for a few weeks.  If you can make a sample image available that would probably be helpful.

I'd suggest clicking the "Notify" button in the upper right corner of this thread if you want to know when there's a response.

[kiekerjan]

Thanks StarGeek. However, I think the issue is simpler than that. The lenstype 50493 was obtained from an e type mount camera. I was looking at the wrong list. Woops. Apologies for the noise.

[kiekerjan]

Actually, I do have more questions. 

If I'm correct, there are three variants of the Sigma 17-70 lens:

• Sigma 17-70mm F2.8-4.5 (D)
• Sigma 17-70mm F2.8-4 DC Macro HSM
• Sigma 17-70mm F2.8-4 DC Macro HSM Contemporary

The first lens has lenstype 24, and the other two lenses have lenstype 128.
My questions:

• Shouldn't there be an entry in the Sony LensType list for the Contemporary lens? As far as I can see these are different lenses, and e.g. lensfun has a different set of corrections.
• There are 2 lenses with the same name, zoom and aperture range with the same LensType (=128). How can you distinguish between them purely from EXIF information? (I know I can use ".ExifTool_config" to "help" exiftool, but then there should at least be an entry for both lenses in the LensType list)

[JosR]

If I'm correct, there are three variants of the Sigma 17-70 lens:

• Sigma 17-70mm F2.8-4.5 (D)
• Sigma 17-70mm F2.8-4 DC Macro HSM
• Sigma 17-70mm F2.8-4 DC Macro HSM Contemporary

The first lens has lenstype 24, and the other two lenses have lenstype 128.

Yes, I think you are correct, although the name of the first one should be "DC Macro", the "(D)" is Minolta terminology.
And indeed, the optical construction of the second and third one are different.

My questions:

• Shouldn't there be an entry in the Sony LensType list for the Contemporary lens? As far as I can see these are different lenses, and e.g. lensfun has a different set of corrections.
• There are 2 lenses with the same name, zoom and aperture range with the same LensType (=128). How can you distinguish between them purely from EXIF information? (I know I can use ".ExifTool_config" to "help" exiftool, but then there should at least be an entry for both lenses in the LensType list)

A separate entry for the Contemporary lens would be nice.
However, the LensType list is based on a LensType number as reported by the lens to the camera. And at this moment, there are 27 lenses, mostly Sigma, that use the same LensType=128 number!!
With the same LensType number and the same lens info 17-70mm F2.8-4, Exiftool will not be able to distinguish between the last two versions.