« on: December 30, 2014, 02:07:02 PM »
Just wondering if anyone here have had AF issues with the Sigma 50 Art and had it successfully repaired, not swapped for a new?
Mine is getting worse and I'm at the very last of my patience with it, so last chance is to perhaps send it for repair.
Mine has been perfect since day one. Got it fairly early. Have shot a lot with 50mm f/1.2 L before.
When you use such a shallow depth of field you have count on some misses no matter what if you are shooting something tight such as a portrait. I take 3 shots to be fairly sure I have at least one spot on. I'd say 2 of 3 in average are good in focus shots.
Also, we tend to use such extreme f-stops when the light is bad (and when the lens is most useful). Try testing the lens at good light and see if it makes a difference. Maybe also rent a Canon before you decide the Sigma that'is broken?
I'm not gonna list all the copies of all the different super fast lenses I have owned and/or used, but it FAR outnumbers the 2.8 and slower lenses I have used. And I shoot wide open 99% of the time. Let's just say we can rule out user error with this specific issue. I'm a strobist so I also use the large apertures in bright sunlight a lot also. You are right in what you say about thin dof and that it requires a bit more focus to nail but it's not the issue here.