(multi-coated)

OM-2000 with mirror and aperture prefire

@ 70 mm setting
Vignetting = B- @ f/4.5, B+ @ f/5.6
Distortion = slight barrel
Aperture Center Corner
f/4.5    B      B
f/5.6    B+     B+
f/8      A-     A-
f/11     A-     A-
f/16     B+     B+
f/22     B      B
Notes: Moderate contrast

@ 135 mm setting
Vignetting = B @ f/5, B @ f/5.6
Distortion = pronounced pincushion
Aperture Center Corner
f/5      B+     B
f/5.6    B      B-
f/8      B      B-
f/11     B      B
f/16     B+     B
f/22     B     B
Notes: Moderate high contrast at the expense of resolution.

@ 210 mm setting
Vignetting = B @ f/5.6
Distortion = moderate pincushion
Aperture Center Corner
f/5.6    B-     B
f/8      B      B+
f/11     B      B
f/16     B      B
f/22     B      B
Notes: Moderately high contrast at the expense of resolution.