Sigma AF 70-200mm f/2.8 EX OS HSM AF
Your problem sounds very much like the one I had with my Sigma 50-500mm where it would just "judder" back and forward but not lock focus on anything.
It went back for repair and has been fine since.
. My Flickr
But then began to focus as it should be, and not focus on failure, and moreover is quite fast.
I appreciate your attention on this issue,.
Best regards
NSANTOS
Member
FIGUEIRA da FOZ PORTUGAL
I just received my new Sigma AF 70-200mm f/2.8 EX OS HSM, I'm experiencing it, and notice that the AF is quite fast, but is very confused and does not focus on AF.
Here someone has the same lens and can give your opinion about this problem because I have to test the lens for one more day and if this is a fault of the lens goes back.
Best regards for every one