Comparing two lenses I have, the discontinued Nikkor 28-70mm 3.5-4.5 AF D and the Nikkor 18-55mm 35-5.6 G ED, it appears the older lens yields a slightly sharper focus on my D7000. I would think the glass in the two lenses are comparable, though the older lens is FX, the newer DX. Would the "mechanical" focus on the older lens be more accurate? Would the focus be more accurate with the camera focusing the older AF D lens mechanically rather than the newer lens being told by the camera how to focus?