Originally posted by luftfluss Each photo has an area of good sharpness. Are you using center-point focus or letting the camera decide on the focus point? For instance, in the photo of the squirrel, the tail looks sharp but the face is soft.
The shot of the building, there's haze. It looks decently sharp, but the further away the subject, the more the atmospheric conditions come into play.
I agree, the lens resolves well - just not necessarily in the area that he was expecting. The so-so swan shot has the ducklings quite acceptably sharp.
Squirrel shot, tail/leaves in the background are in focus not his face (which focus point are you using?)
It is hard to tell ultimate sharpness with the images of the size posted, but I would really check BF/FF with a chart to see if its accurate and adjust in-camera if you have this function.
It appears to back-focus to me.
Also taking shots @ F8 with low shutter speeds is a recipe for motion blur - probably not ideal when you're using them as sharpness examples. These seem to have been coped well with by the SR though.
photozone.de shows some pretty impressive MTF resolution figures for the lens in that price range even @ 300mm - edges are a bit worse but still acceptable. It actually out resolves my medicore 135-400mm sigma @ 300mm in the center range by a smidge but the edges fall short.