Olympus OM 100m f/2.8 Lens Review
Very sharp, outstanding quality lens. This lens is excellent from every aspects very well built, optically superb and very good looking too.Not very common lens, hard to find, almost nobody want to sell it. So small looks an normal 50mm lens.Perform very well as portrait lens or general purpose traveler lens.You able to use on many DSL cameras such as Canon,Olympus etc.
Lens

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Fact Sheet
Vendor name
Olympus
Olympus
Type
OM
OM
Product year
–
–
Focal Min(mm)
100
100
Focal Max(mm)
100
100
Focus Min(cm)
100
100
Aperture Max
2.8
2.8
Aperture Min.
22
22
Barrel length(mm)
48
48
Elements In Group
5 in 5
5 in 5
Diaphragm action
Auto
Auto
Weight (g)
235
235
Filter Size (mm)
49
49
Push on diameter (mm)
60
60
Angular field
24
24

One of my favorite Zuiko lenses, excellent for portraits and isolating little details, outstandingly sharp with good bokeh (out of focus portion of image), and remarkably small and light for this focal length.
Amazingly compact and fairly light, yet the photo quality is excellent. The miniaturization seems to have exacted no optical penalties whatsoever. Mine is an early model single-coated silver nose version, but it is still very contrasty and sharp. I see no obvious faults in any of the photos I have taken.
The 100mm 2.8 Zuiko is a excellent lens.
Very compact, not bigger than a standard lens, easy to carry, well suited to the compact OM camera bodies, not a intimidating nor a threatening appearance like many bigger lenses.
Sharp and contrasty at full aperture, more easy to focus than the 85mm 2.0 Zuiko.