I don't think this lens is special case. For example, firmware v3.20 for A6000 (current) was introduced only to add SEL70-200GM support. Firmware v1.01 for NEX-5T (current) -to add support for SELP18-105 and some FF lenses etc.
So I still think - correction is added by camera firmware upgrade.
But, as I says before - I`m not SONY engineer, so I can only guess.
The new firmware added 'support' for the lens, but what does that actually mean? All it says is:
Improvements over version 3.10:
- Provides new lens support (SEL70200GM)
- Improves stability of operation when using telephoto lenses such as SEL70200GM and SEL20TC
If you look at the
lens compatibility chart , the note says:
SEL70200GM
FE 70-200mm F2.8 GM OSS
- The Exif lens name does not include the letters "GM". If you update the camera system software to Version 3.10 or higher, “GM” will be included at the end of the name.
- When a Teleconverter Lens (SEL14TC or SEL20TC) is attached, the focal length and maximum aperture for the Exif lens name will be listed using magnification values. If you update the camera system software to Version 3.10 or higher, the name of the lens itself will be listed along with the name of the Teleconverter.
- It is available with the camera firmware Ver.3.20 or later.
Note that
support seems to consist of producing the correct Exif info, which suggests that lens correction was already implemented, as I said earlier. I think that the highly distorting SELP1650 introduced additional lens correction data which older cameras weren't expecting; thereafter, all lenses have been corrected with no change to firmware, but not necessarily with the correct exif lens description, probably because these GM lenses have an extra field not present in older lenses.
Sorry - not so. You see, that EXIF correction was introduced in FW 3.10
already, and FW 3.20 continues this. But "support", whatever this mean, is introduced only in FW 3.20. So it is some different things. Sorry, I have not this lens, so cannot check if "support" means lens correction or something else. But I bet - it`s all about correction, both with tele convertors and without.