Messages

I just tried a Sigma 28-105/3.8-5.6 UC-III of 1999 vintage. On 5D Mark II the aperture does not operate. I got an Err 01 after the exposure. With Metabones Mark IV adapter and Sony A6300, however, the aperture works fine. So one way to use those very old Sigmas is to use them on a Sony. Metabones issues the 0x13 command to move the aperture for Canon lenses but use 0x12 instead for the old Sigmas.