I just scored a Tokina ATX 400mm f5.6. The AF version for Nikon. I had often wanted one but never enough to buy one. Well i should have bought one years ago. it appears to be a very well made lens and looks contrasty in the viewfinder. its much smaller than I expected and easy to handhold, not that I would want to. The AF is internal and quick enough for me. I will have to report back after I run some film through it.