Re: [OM] OM-3 & 3Ti Shutter/Aperture vibration

Subject: Re: [OM] OM-3 & 3Ti Shutter/Aperture vibration
From: Joel Wilcox <jowilcox@xxxxxxxxxxxxxxxxxxx>
Date: Mon, 09 Aug 1999 09:25:49 -0500
At 08:17 PM 8/9/1999 +1000, Ross you wrote:
>G'day all
>After reading all of the messages recently relating to the vibration of an 
>OM-1 with lenses >50mm when tripod mounted, even using the mirror lockup, I 
>am left wondering how good the OM-3 & 3Ti are in this regard.  They have 
>neither mirror lockup or mirror & aperture prefire.  (For that matter 
>neither does the OM-2/2n).  Does this mean that the full potential of the 
>longer/bulkier Zuiko lenses can not be realised with these cameras when 
>used on a tripod?

I think it can be realized with telephoto lens support and/or proper
shooting technique such as hand dampening and using one's finger to release
the shutter rather than a cable release. It depends entirely on the shutter
setting, of course.  The vulnerable speeds are 1/2 to 1/30.

>What about the OM-4/Ti when prefire is not practical, eg macro shots 
>waiting for a lull in the breeze.  With the extra magnification of a macro 
>setup, the shutter/aperture vibration with a lens like the 90mm would 
>surely be pronounced.

Yeah, this is tough.  The OM-4Ti shutter is smooth though, so using hand
dampening and finger release at the scary shutter speeds I think is the
best plan.  Any mirror lockup scenario seems to me to be applicable only in
dead still settings.

>It seems that for tripod mounted photography with lenses longer than 50mm, 
>if one is doing critical work for enlargement, the OM-4/Ti or OM2000 using 
>prefire are the only real choices.  I had one day aspired to own a 3Ti if 
>some ever hit the second hand market at affordable prices, but maybe I'd be 
>better just sticking to the 4/4Ti.
>Ross Waite

To summarize the problems:  MLU on the OM-1 does not nullify vibration at
critical speeds because it isn't the source of the problem, which is either
caused by aperture stopdown or the horizontal shutter. The timer/MLU on the
OM-2S/4T could improve stability because it nullifies aperture stopdown
vibration, or the shutter might have been improved.

I sort of theorize that it's the latter. I'd guess that the electronic
"driver" on the OM-2S/4T shutter is smoother than the mechanical
counterpart of the OM-1.  Can't say as to the OM-3(T) since I don't know
how it compares to the OM-1.

I also wonder whether NOT using MLU with the OM-1 at the critical shutter
speeds but instead using telephoto lens support where one can and good hand
dampening and finger release techique isn't the proper way to go.
Specifically, I wonder whether the synergy of mirror "slap", aperture
stopdown, and shutter release might not produce a better result than one
gets from removing one of these elements.

I would be fun to have a special ADITL dedicated to Olympus mechanical

Joel Wilcox
Iowa City, Iowa USA

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