Re: [ATM] lensmaker for a very long focus objective

["gfphoto" <gfphoto1@earthlink.net>]

> We will attach the objective to a flagpole or something. An existing pole
> is 100' from a likely viewing area, so I suggested an objective with 100'
> focal length.

>>However, a flagpole bends in the wind. Without something to keep the two 
components (objective and eyepiece) a fixed distance from and square to each 
other, viewing would be impossible. A 1 degree tilt of the objective would 
result in the focal plane moving about 1.5' to the side!

Just trying to learn here...

Couldn't this bending be easily compensated for by mounting the eyepiece on an identical flagpole? Of course making sure that both are equally exposed to the wind - perhaps requiring the removal of any nearby structures, or their relocation underground...

Cheers,

Gary Fuchs
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