OK, so I usually don't spend (a lot of) time measurbating, but with Sigma lenses you kinda have to do it, because you never know what you are going to get :biggrin:. I recently purchased a Sigma 30/1.4 for my D40. While you don't buy a lens like that for sharpness, my copy seems to drop off rather sharply below f/2.8. The whole purpose of this lens is to use it down there, so I am wondering... What do Sigma 30 owners think --- par for the course or send to New York for tweaking? I don't want to play the Sigma lottery and exchange for a different copy.