Hello all --
A little while ago I wrote the list asking if anyone knew the spec length
of the aperture coupling pin on OM lenses, since I had a lens with erratic
behavior and (seemingly) a short pin. Got some interesting comments, but
little hard data. In a recent digest, I noticed someone who returned an
OM-4T because "the lens sensing nib on the collar of the mount was too
close to tolerance and going spastic". Aha! Maybe someone knows what the
spec is!!! If so, please share! For what it is worth, here are the
measurements I've made on my OM-4T and lenses I've been able to check:
DescriptionAperture Pin Interface (mm)
Olympus OM-4T body-6.0
Olympus Zuiko Auto-Macro 50/f3.5 Lens7.1
Olympus Zuiko 75~150/f4 Zoom Lens7.2
Olympus Zuiko Auto-S 50/f1.4 Lens7.0
Tokina 35~105/f3.5-4.3 Zoom Lens (OM mt)7.0
Tokina AT-X 28~85 f3.5-4.5 Zoom Lens (OM mt)7.0
Tokina AT-X 50~250 f4-5.6 Zoom Lens (OM mt)7.0
Vivitar 80~200/f4.0 Macro Zoom Lens (OM mt)6.2
Vivitar Series 1 70~210/f2.8~4 Zoom lens (OM mt)6.9
The Vivitar 80~200 is the lens that gives me problems.... not too
surprising, given these measurements. Would be interested in anyone who has
similar measurements from their cameras/lenses, or, as I said, has official
Olympus spec data.
P.S. These measurements are a little on the crude side - I made them using
a tire tread depth gauge!
|