I just got a SIGMA 17-70 1:2:8-4 DC (C) lense. Mount looks very much like Canon EF (S) but it's smaller. Added a foto from a 70-200 EF to compare. Anybody knows what this mount is for? Many thanks in advance

Sigma measure

Canon measure

Sigma Objectiv Image1

Sigma mount Image1

  • could it be a sigma SA mount?
    – Patrick
    Feb 3, 2020 at 21:42
  • EF-M perhaps? Its 47mm throat diameter looks similar to your measurement
    – Nate S.
    Feb 3, 2020 at 21:42
  • that's what I thought first but SIgma says on there webpage it would be only available for: Canon EF-Mount, Nikon F-Mount, SIGMA SA-Mount, Pentax K-Mount, Sony A-Mount
    – Patrick
    Feb 3, 2020 at 21:53
  • SA seems likely then. Take a look at the linked picture from the comment on this answer; does that look like what you've got?: photo.stackexchange.com/questions/65303/…
    – Nate S.
    Feb 3, 2020 at 22:15
  • 1
    @NateS. This discussion in comments is a good example of the site's guideline: Please put your answers in the answers section, even if they're short
    – scottbb
    Feb 4, 2020 at 2:43

1 Answer 1


Thanks @Nate S. for his answer.

This looks like the same thing, so yes, SA: https://www.worthpoint.com/worthopedia/sigma-17-70mm-2-4-macro-dc-sigma-sa-1791976047

Solution is Sigma SA Mount

  • Sigma SA reportedly uses the same communication protocol as Canon EF, which explains why it looks like an EF mount from an alternate universe.
    – xiota
    Feb 4, 2020 at 3:48
  • IIRC you have have the mount changed by Sigma service. Nice lens, that's my "standard" one. Just a bit soft at 17mm.
    – xenoid
    Feb 4, 2020 at 10:25

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.