I'm afraid I have to post a negative review of this lens.
The one I got was shockingly bad. It struggled to focus correctly on anything and even the few it did correctly focus on there was very poor image quality, no definition, poor contrast, in fact little detail to be seen.
I can only assume the lens was faulty. I returned it within 48 hours of receiving it.
The supplier said it wasn't faulty, but if they had admitted it was, they would have had to pay for the return postage cost. I've got dozens of sample shots that prove it was.
I've bought four Sigma lenses, two of the four were faulty from new. I think that says something about Sigma quality control. This time I was so angry I refused a replacement. My next lens will probably be an off shade of white rather than Sigma black.