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posted to rec.boats
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First recorded activity by BoatBanter: Jul 2006
Posts: 4,727
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"Boat" telescope
"hk" wrote in message
. ..
wrote:
On Aug 21, 5:39 pm, (Richard Casady)
wrote:
On Thu, 21 Aug 2008 10:49:35 -0700 (PDT),
wrote:
On Aug 21, 1:46 pm, wrote:
My daughter is sick so I have to stay home if she needs me. There is
light rain from Fay so no working on the boat.
So..........start a project I have been planning, a boat telescope.
I like casual astronomy just a little better than 7X50 binocs and I
know about optics and ground a telescope mirror when I was a kid. So,
this project is a 4" diameter mirror of only 20" focal length and low
magnification for very wide field of view.
After 1st half hour of rough grinding, I have a definite bowl in the
mirror.
I tried that liquid mirror thing once, or at least an infra-red
variation. I put a bowl of epoxy on my old turntable and spun it for
several hours till it hardened. It sorta worked but I did not manage
to get the bubbles out so he surface was covered with tiny pockmarks.
Put it under a bell jar and pull a vacuum on it.
Casady
I was only 17 when I did that so had no bell jar.
Do I understand this? Someone is going to mount a telescope on a small
boat?
Hehehehehehe.
Fascinating place, rec.boats is.
Ought to be useful when the boat is on a trailer in the driveway.
I take my telescope with me at times boating. As well as the spotting
scope. Lots of times we are beached and can use the good optics.
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