Quote Originally Posted by puderse View Post
The question is this: Is there an optimal distance from the lens to test performance for comparitive reasons?
Well, I don't think the distance will have much effect on center sharpness, but sure, corner sharpness might well suffer noticeably if you are too close.

I suppose that when one runs the calculations to design a lens, a particular reproduction ratio (and therefore focusing distance) is assumed. If the lens is to be used at very small working distances then additional corrections are warranted (e.g. a floating element).

Why don't you just try it and see? I'd be curious what numbers you get at close focus versus far. Obviously a macro lens should shine at ~1:1, whereas a tele should suck there. But I'd be interested in the real numbers. My own anecdotal experience suggests that apo-corrected lenses shine at all distances, whereas non-apo/uld/ed lenses tend to have issues at close focus. But I do not shoot charts....