Acquired a Mamiya 45mm F2.8 "S" wideangle lens about a year ago, to go with my 645E setup. I do a fair amount of landscape photography, camera tripod mounted, and with the mirror locked up. On the finished negs, the center portion is extremely sharp, but about halfway out to the edge of the frame, the resolution drops-off significantly. Stopping down to f8 ~f11 helps a bit, but the soft edges are still noticeable. For testing purposes, I have shot multiple test rolls of highly detailed contrasty subject matter from f2.8 to f22 , and the 45mm's poor perfomance is consistent; sharp in the center, soft edges. I was wondering if other owners of this 45mm wideangle lens have experienced similar performance. Any comments would be appreciated. - Phil Eide zdf33 at hotmail.com OBTW, I also have the Mamiya 55mm f2.8 wideangle, and the performance is superb, sharp corner to corner once you stop down to f5.6 ~f16, far better than the 45mm.