I've only had the Zeiss Planar for a few months now, but have taken quite a few shots I really like with it. I've noticed the shots I really like are typically at f/2.8 or wider. The lens is plenty sharp when stopped down farther and still has the great rendering.
I've looked at some of the shots to compare and the element I think I like so much at f/2.8 and wider is the vignetting (in addition to thin depth of field). It gives presence to image's subject. Most reviews look at the vignetting as being a weakness.
What do you think? Does anyone else appreciate the vignetting within a couple stops of wide open?
Dave