🚀 go-pugleaf

In article <29178@oasys.dt.navy.mil> roscoe@oasys.dt.navy.mil (Andrew Roscoe) writes:
>I'm in the process of building a large aperture Dobsonian.  I am
>at the point where a decision must be made as to the optical
>company from which I should purchase the mirror.  I am considering
>four companies, Galaxy Optics, D & G Optical, Pegasus Optics, and
>Handmade Telescopes, all of which sell a 20 inch mirror for about
>$2000.  My question is does anyone have any experience with these
>companies, especially where mirror quality is concerned?

I ordered a 20" f5 and secondary from Galaxy in 1991. I got the mirror on time
and the optics appear to be pretty good. I have not yet objectively
tested them. They came with a lifetime warranty.

>In the same vein, this telescope is an open truss design and I have
>read that one's body heat will seriously degrade image quality. 
>I have been considering the use of bubble wrap as a shroud.  Is
>this feasible?  Is it practical?  Will I still need a black cloth
>shroud to eliminate stray light?

You need to cover the truss in any event to prevent stray light.
I have not found body heat to be a big problem.

>In their advertisements Astro-Physics published testimonial letters
>describing Enke's division as being easily observed through their
>6" apochromatic Starfire telescope.  Is this possible?  Will I be
>able to resolve Enke's division with my 20" f/5 Dobsonian?

Astro-Physics makes beautiful stuff. If I could afford it I'd buy one
and permanently mount my 20". I probably will permanently mount my 20
since it's a pain to put up and tear down. But, the rule of thumb is
given good observing conditions, nothing beats aperature. Enke is
easily seen.
-- 
=================
No regrets, ever!			| Tom Glinos @ U of Toronto Statistics
For down that path, lies madness	| tg@utstat.toronto.edu