On Aug 22, 11:26*am, wrote:
On Aug 22, 1:15 am, "Calif Bill" wrote:





"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.

The idea here is very low f# and very low magnification. *In general,
the motion of a boat at anchor is not as much a problem for such
casual viewing as is the shakes of a person holding a scope. *This
scope is intended to be held in ones lap while sitting down. *Foam
around the scope base will be used to dampen shakes from the person
holding it. *This is not for serious astronomy but only for very
casual looking at stuff. *I have an 8' scope on a mount for serious
stuff. *So Harry, do the math before you criticize.- Hide quoted text -

- Show quoted text -

Harry is just trying as usual to be the biggest asshole around. He
doesn't know what he's talking about and doesn't care to, he just
wants to be an ass.