Here are my first impressions and observations from working with the lens:
The switch-over between AF and MF (by pulling the focus-ring) is not state of the art, but works quite well and intuitively while looking through the viewfinder: as soon as you notice that the focus-ring doesn’t give way to your manual focusing efforts, you remember to pull.
AF is a little noisy and slow, but that’s ok with me. In low-light the focus normally finds the target, albeit that needs some "thinking" from time to time. Focus quality will be judged later.
The focus-ring doesn't turn with AF, that's good
The lens is much easier to get your hands around than the Sigma 12-24mm. The rubberized rings feel good.
The lens has no dof-marker.
You can see pictures taken for the test here
. It will be slowly filling up over time. I'll also be placing "mishaps" to give you a feeling of the "hit-rate" of the lens/body-combo in automatic...