I read the article Mike linked. The unfortunate problem with the
measurements is that his time scale typically spans 1 sec making it
hard to tell what happens in 1/100 sec.
Hmmm ... Markins is run by a photographer who can hand hold a camera
about 4 times steadier than the author of the article who is also a
photographer.
The author actually measured vibration. It looks like he has
documented that heavy very stiff mounting does produce a sharper image
(the time base being the major problem). Basically turn your camera
and tripod into a single very heavy, very stiff object with no parts
that can move relative to others. He is coming from the F = M x A or
perhaps acceleration = force divided by mass viewpoint.
Other interesting points with few graphs if any to support them; new
autofocus lenses built with easy movement for autofocus are a problem
when trying to get a very sharp image, solid metal to metal clamping
is much better than cork or rubber pads, the big heavy medium format
stuff with loud mirror slapping have less vibration than the 35mm
stuff, even the wind from a desktop fan has a dramatic influence on
sharpness ....
It is worth reading and thinking about. ... and yes a large lead
weight solidly attached to the camera would give better test results
but the Markins tripod plate is intended to provide a very solid union
between the tripod and the camera.
-jeff
On 3/11/07, usher99@xxxxxxx <usher99@xxxxxxx> wrote:
>
> Hi,
> In armament acquisition mode for trip in a couple months. My very modest
> Velbon was not anywhere near sturdy enough for the Tam 400 f4----I doubt I
> can lug it this trip though. The quite light Vel does OK even with the Z.
> 50-250 as long as I bring my pellet (bean) bag. Thinking of Gitzo 1257 and
> adding the Markins base plate, though still need a hands on trial, if
> possible. I need things fairly light as I take over 60% of shots on trips
> due to time constraints. Hoping my choice will also be OK with the Tam 400
> as well. Seems some did not like the tripod (FM site) due to vibrations but
> was quite good with the markins gizmo. Clearly some of the goals are in part
> mutually exclusive though I'm not sure if the proposed compromise is
> reasonable. Wanted to check here first. Any comments appreciated.
>
> http://www.markinsamerica.com/MA5/TB-20.php
>
>
> Mike
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