Your problem is almost certainly vibration. If you look at Gary's tests
of this lens, you will find a whole series of tests of the 200/4 with
different supports and camera bodies. The results range from poor to
excellent, all with the same actual lens. This is a problem with all the
longer lenses, but particularly true for the modest speed mid-longish
teles. There are 3 sources of vibration generated in the camera itself,
mirror, diaphram and shutter. All create vibrations which may result in
body and/or lens movement during the exposure. Some body/lens combos
seem to have sympathetic vibrations triggered by one or another of these
sources, while others respond very little of actually damp them out. The
200/4 is sort of the "poster glass" for this phenomenon.
Vibration and wind can also cause sympathetic vibration in tripods,
particularly lightweight ones with aluminum legs.
Although Gary had to do his tests with tripod and cable release to
eliminate an unquantifiable variable, you don't. Oly says for all their
tele lenses, " When using a tripod, hold the camera steady with both
hands and press the shutter release with the ball of finger, not with
the cable release." I would add to that, "and press down on the camera
while holding it." What this does is provide broad spectrum, multi
frequency and waveform shape amorphous wetware damping by your body,
which is quite well suited for the task. The reason I add the downward
press, is to help damp tripod leg vibration as well. Unlike the other
solutions, this also addresses shutter induced vibration.
Mirror lock-up on the OM-1 alone helps, but not that much. MLU and
aperture pre-fire on the later bodies that have it helps more. I believe
that proper wetware practice is more important than mirror and aperture
solutions, but obviously they complement each other.
You may find that using this technique will also improve you results
from the 35-105, especially at the long end. Gary's test of the 35-105
showed a significant difference in results at 105mm between an OM-1 with
MLU alone and an OM2000 with mirror and aperture prefire. Of the OM-1
test, "Notes: Very contrasty, but length of lens on an OM-1 results in
lower SQF grades due to vibration." With this indication that this lens
too is subject to this problem, proper tripod technique should also
improve results with it.
Moose
Simon Worby wrote:
>I've just had some photos back taken with my new-old 200mm f4 Zuiko. I have
>two shots of the same thing, one fast speed, low DoF (probably f4), and one
>low speed, high DoF (probably f22). The latter is blurred -- like camera
>shake, but I know for sure I took it on a tripod with cable release. IIRC
>speed was around 1/4 second. All the small aperture shots taken with this
>camera/lens combination (OM-1N & 200 f4) are blurred; all were taken using
>cable release and tripod. Small aperture shots taken with my 35-105 lens seem
>fine (same camera).
>
>Is it possible to have a lens that is "broken" at small apertures? Would the
>sympoms be consistent with mine? Is there any further way of telling /
>conclusive tests I can run?
>
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