Sirrith wrote in post #15565559
The lens works great on my 5DIII. Very small percentage of faulty copies made to appear more serious than it really is by the loud voices of those who are discontent.
I had one that was consistently inconsistent on my 5D3. Specifically at longer focal distances. It has been replaced with another that, under normal shooting conditions, seems to be doing just fine and dandy. I would doubt it is a 5D3/siggy 35 compatible issue. While it is totally conceivable that there are some funky copies out there (I had one...I think), I really think that 1) the lens is under extreme scrutiny due to the fact that the sigma lens manufacturer is digging itself out of a hole as far as QC is concerned and 2) the fact that the the new siggy 35 is so totally out of this world sharp as hell wide open that people (myself included) expect every shot to be perfect. Even with the best lens out there you don't score the money shot every time. There are many factors that go into "nailing" the money shot...lighting, contrast, distance to subject are but a few. So when I get a shot that isn't quite as sharp as I know the lens is capable of, under the aforementioned extreme scrutiny, I would like to blame the lens and not the shooting conditions.