[Azorel]

Thank you for sharing your experience with this lens. I knew something about Sigma focusing problems but I did not imagine they are so serious. I own a Sigma 17-70/ 2.8 and I recently tested it in a trip to Europe. I mainly used this Sigma and a Tokina 11-16/2.8. Tokina gave me some focusing problems, one out of 20-25 pictures, which is acceptable. But in the same conditions Tokina can give different results, let say "normal" quality pictures, and some that are totally outstanding. The quality and depth of the colors are unique and impossible to replicate with other lenses. I ended up shooting in continuous mode and keeping the best copy. Sigma 17-70 did not give me noticeable focusing problems but it was not capable to compare with some Tokina outstanding pictures. The Sigma results were very constant and I used single shoot mode for Sigma to save time deleting multiple identical copies. Reading your replies I should consider myself very lucky that the Sigma 17-70 copy I own is pairing perfectly with may Canon body. I may give up on Sigma 30/1.4, I do not want to force my luck. Twice in a row to get a perfect copy it is hard to believe it will happen.