(single-coated) OM-1 with mirror lock up Vignetting = A-? Distortion = none to very slight pincushion Aperture Center Corner f/4 D+ D f/5.6 D+ C- f/8 C C f/11 B- C f/16 B B- f/22 B C+ f/32 B C+ Notes: Slightly longer shutter speeds at a given aperture versus the 200mm f/4 multicoated test. Low contrast images. 200mm f/4 Zuiko (single-coated) with Olympus 2X Teleconverter OM-1 with mirror lockup Vignetting = B+? Distortion = pincushion Aperture Center Corner f/4 (8) D+ D- f/5.6 (11) C C- f/8 (16) C+ C- f/11 (22) B- C f/16 (32) B- C+ f/22 (45) C+ C f/32 (64) C C- Notes: Slightly longer shutter speeds used at a given aperture versus the 200mm f/4 multicoated test; thus the effects of camera shake lessened. Low contrast images. No performance degradation at f/11 over the 200mm f/4 without teleconverter.