Sigma 50mm Art on Canon 50D Focus issues

[keriboi]

Have lots of problems getting a Sigma 50mm Art to focus with my old 50D. One in ten shots would be in focus.

The lens is incredible when its on. Best shots I got was using a tripod and using the 10 x magnification in live view to manually focus.

Have I got any unlucky sample of do I need to get myself a 5D III

Love the depth of field, heres a good shot at 1.4 http://500px.com/photo/72102947/sigma-art-by-dane-hawker?from=user_library

 

[wickidwombat]

have you tried calibrating the lens with the sigma dock?

 

[Invertalon]

Prob the Sigma, not the camera...

 

[Viggo]

Exchange it, calibration does not help if it misses inconsistently and it sounds a lot like the first I had.

 

[skitron]

I had a 50d and 5d2 at the same time and was able to compare focus accuracy and was able to test and repeat results showing my 50d had a much larger in focus zone than the 5d2. This meant I had not so good percentages of in focus shots with my 50d using fast primes while the same lens did fine on my 5d2 and now 5d3. I liked the 50d except for that fact. It was fine with smaller apertures.