Re: [APML]: barndoor tracker question

["Tom Krajci" <krajcit@det5wg57.barksdale.af.mil>]

> From:          "Richard Keppler" <rkeppler@telusplanet.net>

> ...The mount would have
> to be quite beefy as well, with some sort of very heavy duty tripod to
> eliminate flexure and vibrations due to wind.  

Legs were two by four's.  ;-)  Nothing exotic, just beefy.

> As an aside, how do you
> manage to support such a long focal length lense, such as the 300mm
> without camera flexure.  A friend has a 280mm f/2.8 which requires a
> platform specifically designed to support the lense and camera in order
> to eliminate the camera body flexure due to the mass of this huge
> beast...

My 300mm f/4 lens is much lighter so that wasn't an issue with me.  
But my home made tripod was far sturdier than anything else I could 
get for the cost of a few lengths of 2x4's from the hardware store.  
It could handle moderate winds with little/no problem.

One other thing, this barndoor was so large that it needed a 
counterweight arm on the driven board so the threaded rod was only 
pushing with a few pounds of force.

Tom Krajci

Capt Tom Krajci
B-52 Intelligence Officer
"In God we trust, all others we monitor!"
http://spur.barksdale.af.mil