MT Shooter wrote:
Its an very old film lens from 1989 through the late 1990's. Its also EF mount so I have no idea how you plan to try it on an F1 film body, it simply will NOT fit.
Also note, many of those old Sigma EF mount film lenses will NOT AF on some of the newer Canon DSLRs unless Sigma has updated the AF chip in the lens. And this one is no longer supported by Sigma due to its age so such a chip update will not be possible. You really need to test it with a few newer Canon EF DSLR bodies.
The AF is not the problem ( although on a lens this old it could be) - the problem is using an aperture smaller than 2.8 with a Canon digital body - without a chip upgrade.
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