Nikon Nikkor 43-86mm f/3.5 Non-AI
Nikon F2 w/ mirror lockup and diaphragm prefire

@ 50mm focal length

Vignetting = B- @ f/3.5, B+ @ f/4, A- @ f/5.6, A @ f/8
Distortion = distinct waveform

Aperture Center Corner
f/3.5    B      C
f/4      B      C
f/5.6    B+     C+
f/8      B+     C+
f/11     A-     B
f/16     B+     B
f/22     B      B

Notes: Moderately low contrast at f/3.5 & f/4; moderate contrast @ f/5.6, f/8, f/16, f/22; moderately high contrast at f/11.