Canon FD 35mm f/3.5 S.C. breech mount
Canon EF with mirror and diaphragm prefire

Vignetting = B+ @ f/3.5, A- @ f/5.6, A thereafter
Distortion = barrel

Aperture Center Corner
f/3.5    B+     B-
f/5.6    A-     A
f/8      A      A
f/11     B+     B
f/16     B      B
f/22     B-     B

Note:
moderate contrast at f/3.5 and f/22;
moderately high contrast at f/5.6 through f/16.