Hey all. I took some focus tests with the 3 AF lenses that I have:
FA 50 1.7
FA 100 2.8
DAL 18-55
I purchased the 50/1.7 over the 1.4 because it was supposed to be sharper wide open. Stopped down, it's fantastic, but wide open it's pretty ugly. Not just soft, but some sort of aberration going on. Is this a bad lens, or is this typical for the 1.7?
Second on the list was the kit lens. As expected it's pretty soft wide open, esp at 55. What's interesting though, is that the focus offset changes through the zoom range. In fact, with the camera and target fixed, you can intermittently press the focus button while zooming out. Focus doesn't change from 55 down to 28, but from 28-18 it (audibly) refocuses. If anything, with the DOF I'd expect that sort of thing to happen at the other end of the zoom. The target was centered, these are cropped 100% and to the side so the markings show. Is this atypical? Can anyone else replicate?