I discovered a quick-and-dirty way to reduce 16" mount vibrations
last night (saw the vibrations subject line while cleaning out my
mailbox). The Science Center's pier-mounted 16" is located on
a fifth floor balcony, where it picks up building vibrations that
make higher-than-100X difficult to use except when the building is
closed and no elevators are running. When I pulled downward on the
housing of the star diagonal with about five pounds force with my
finger, the vibration amplitude was reduced by at least 95%. The
main use of the scope at the moment is to show planets or lunar
features, visually, to visitors at the Center. I think it might be
possible to solve the vibration problem more practically (for visual
observing, anyway) by hooking the diagonal to the base of the pier
with a bungee-cord-and-rope combination that has an appropriate spring
constant. Or maybe by suspending a five-pound weight on a bungee cord
on the diagonal to simulate finger pressure.

If it works, I'll send pictures of the device to mapug.com.

This brings to mind the possibility of a dynamic anti-vibration unit.
I realize one of these is already marketed by SBIG under the name
"adaptive optics" unit. But maybe an electromagnetic inertial device
mounted on top of the forks, using feedback from a CCD autoguider,
would be cheaper than movable mirrors controlled by an autoguider.
Sort of an automated finger tuned to the vibrations. Doesn't have
the same panache as a bungee cord on the diagonal, however.

RP
Pittsburgh PA


P.S. Doc, how about a night-blooming Cereus for your garden? Or
some of the many other night-blooming species. You could have
flowers and stars at the same time, if that wouldn't overburden
your retired heart. ;-)

View index by [date] [author] [subject]
Previous message: Re: [M]: RE: Re: RE: Shop Manual for Meade Telescopes - I GOT IT!, R. A. Greiner
Next message: [M]: LX200 ScopeSaver/Mounting Assistant, William R Wood
Next message in thread: Re: [M]: 16" Mount Vibrations, gardening, and adaptive optics, R. A. Greiner