Noflexar 600mm f/8 (Novoflex System)
OM-1 with mirror lockup and second tripod supporting hood
Vignetting = B+ @ f/8, A- @ f/11
Distortion = none
Aperture Center Corner
f/8      B-     B
f/11     B      B
f/16     B+     B+
f/22     B+     B+
f/32     B      B-
Notes: Moderately high contrast throughout aperture range; good balance on tripod, although difficult to stabilize with a single tripod;
difficulty in focusing in overcast sunlight (EV12) due to dark viewfinder image.