Minolta MD 50mm f/1.7 (plastic body)
X-700 with self-timer
Distortion: none
Vignetting: C @ f/1.7, B @ f/2, B+ @ f/2.8, A thereafter
Aperture Center Corner
f/1.7    D+     D
f/2      C-     D+
f/2.8    C+     C
f/4      B-     B-
f/5.6    B      B
f/8      B      B
f/11     B+     B+
f/16     B+     B
f/22     B+     B
Notes: Low contrast at f/4 and f/16; moderately low contrast at f/2.8 and f/5.6-f/11; moderate contrast at f/2 and f/22; moderately high contrast (probably due only to an underexposed slide) at f/1.7. Perhaps a bad lens sample - needs retesting with another sample.