[Leica] Vibrations

["Rod Fleming" <rodfleming@sol.co.uk>]

Hi


Jim Brick wrote


>How about a
>wooden glockenspiel?


Yup. It's called a marimba. Sounds very nice too. Wood resonates just fine
under the right conditions, as any guitar player, pianist or violinist will
affirm.

There are a lot of reasons why this thread is becoming a tad academic, but
hey, why not. If you want a really really completely vibration free camera
support, then one exists- it's called a beanbag. Why do you think long range
target riflemen use them? Not to mention their popularity amongst wildlife
photogs.

However they are slow to use, awkward, require some handy and conveniently
shaped topography, and considerably limit camera position. But they sure are
stable.

With very long tele lenses, and the quickest and easiest way to stabilise a
camera and lens on a tripid is to add a monopod- with very long lenses you
support the lens with the tripod and either attach the mono pod to the
camera or use a special adapter to support the end of the lens. It's very
effective, but a pig to line up.

A great deal of the vibration seen when using long lenses will come not so
much from the trip of the shutter, but from wind induced vibration. It can
be a real problem sometimes. Watch news footage of say, a plane hijack or a
prison seige where the camera is a long way away- now that camera is on a
robust support, but you will still see wind-induced movement, unless it's a
flat calm. (I write from Scotland. We don't do a lot of flat calm round
here.)

Also remember that vibration has to do with harmonics, and these can to some
extent be damped out by suspending a mass by a flexible link- a string bag
full of stones hanging from a strap is pretty good, and has the advantage of
being very light. You can use a camera bag, but I prefer the string bag.
Varying the length of the strap has a noticeable effect.

Which is not to say that either wood or carbon fibre is not a good thing- if
it saves weight, that's a plus. I remember reading, somewhere in the dim and
distant, that weight for weight wood is much stiffer than metal (like
several times stiffer)- I suspect that this inherently greater rigidity is
the real reason why wooden tripods are acclaimed as they are.




Cheers


Rod