This information originally
Popular Photography Zuiko Lens Tests, compiled Sun Apr 5 22:45:40 EDT 1998 versio.
50/1.8 MC (5/91 p. 47): (no information included!)
This information extracted from a post by Gary Reese (pcacala@earthlink.net) Midwest Biosurveys, Las Vegas, NV USA
Updated: April 22, 2002. Do not know the original data source.
50mm f/1.8 Zuiko (single-coated) OM-1 with mirror lockup
Vignetting = B
Distortion = slight barrel
Aperture Center Corner
f/1.8 D+ Bf/
2.8 C+ Bf/
4 B B
f/5.6 B B
f/8 B B+
f/11 B+ Af/
16 B+ ANotes:
Slightly soft contrast.
50mm f/1.8 Zuiko (single-coated) OM-4T with mirror and aperture prefire
Vignetting = B @ f/1.8, A @ f/2.8 and thereafter
Distortion = slight barrel
Aperture Center Corner
f/1.8 B Bf/
2.8 B+ B
f/4 B+ B+
f/5.6 B B+
f/8 A- Af/
11 B+ B+
f/16 B B
Notes: Moderate contrast at all apertures.
50mm f/1.8 Zuiko (multi-coated, earlier MC variant) OM-2000 with mirror and aperture prefire
Vignetting = C+ at f/1.8
Distortion = none
Aperture Center Corner
f/1.8 C C
f/2.8 B- C+
f/4 A- Af/
5.6 A+ Af/
8 A+ A
f/11 A- Af/
16 B+ B
Notes: Extremely high contrast at f/5.6 to f/8, high contrast at f/4 and
f/11, moderately high contrast at f/2 to f/2.8 and at f/16.
50mm f/1.8 Zuiko (multi-coated, late "Made in Japan" variant) OM-1 with mirror lockup
Vignetting = B
Distortion = moderate barrel
Aperture Center Corner
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http://members.aol.com/olympusom/lenstests/default_m.htm 1/30/2008
f/1.8 C- C
f/2.8 B- B
f/4 B B+
f/5.6 A- A
f/8 A- A
f/11 A+ A
f/16 A A
Notes: Moderately high contrast and extremely high resolution.
OM-2S with mirror and auto diaphragm prefire, serial number 3694244,
paired comparison with sample below to examine potential production
variation; identical coating
Vignetting = C- @ f/1.8, A- @ f/2.8, A thereafter
Distortion = slight barrel
Aperture Center Corner
f/1.8 B C
f/2.8 A- B+
f/4 A+ A
f/5.6 A Af/
8 A Af/
11 A- B+
f/16 B+ B
Notes: High contrast at f/1.8 to f/2.8 and f/11 to f/16, very high
contrast at f/4 to f/8.
OM-2S with mirror and auto diaphragm prefire, serial number 5235157,
paired comparison with sample above to examine potential production
variation; identical coating
Vignetting = C @ f/1.8, A- @ f/2.8, A thereafter
Distortion = slight barrel
Aperture Center Corner
f/1.8* B Cf/
1.8 B+ C
f/2.8 A Bf/
4 A+ Af/
5.6 A Af/
8 A Af/
11 A- B+
f/16 A- B+
Notes: Moderately high contrast at f/2.8 and f/8 to f/16, high contrast
at f/1.8, very high contrast at f/4 to f/5.6. * = with an Olympus 1A
filter that "passed" a vertical autocollimator test; lens was
refocused after attaching the filter; no detectable contrast
difference with and without filter.
I must caution that unless test conditions are identical (testing organization, methods) it is difficult to directly compare on the basis of the subjective letter grades that
Popular Photography or
Modern Photography used to publish. MTF is much more objective in nature, be still subject to the variances of the test conditions and equipment,.