(multi-coated)

OM-1 with mirror lockup

Vignetting = B
Distortion = none

Aperture Center Corner
f/2      C      C
f/2.8    C      B-
f/4      B      B
f/5.6    A      A-
f/8      A+     A+
f/11     A      A
f/16     A      A-

OM-2000 with mirror and aperture prefire, same lens as above

Aperture Center Corner
f/2      B-     B-
f/2.8    B-     B
f/4      A-     A-
f/5.6    A-     A
f/8      A+     A+
f/11     A      A-
f/16     A-     B+

Notes: Moderate contrast at f/2, f/2.8, f/4, f/5.6, f/16, moderately high contrast at f/8 to f/11. Paired comparison to the Leitz 50mm f/2 Summicron-M in the Other Camera Manufacturer's Lenses section, with differences significant at the 1/3 grade level.