Re: (ATM) What to do with .......

[Bob Madden <madden@netcom.com>]

Peter, you are sorta on my track. I was looking at a Dahl-Kirkam design
this after noon and I began changing my mind. I gotta look some more, but
couldn't I get a lens from Ed Sci and not have to grind and polish that
part - only the primary? Well, once I saw a picture of Robert Cox (I
think) with a small foldable telescope like I'm talking about. I'm not
necessarily wanting a foldable one, just small - and I want to test my
skills more. So tell me more about my idea of using a plano lens of the 
correct radii, Please?

Friendly Bob

):-{])) <----   madden@netcom.com
                madden@svpal.org
 Remember amateur astronomers:
"keep looking for the next Universe"

On Sun, 15 Oct 1995, SCN User wrote:

> The formulae are in Rutten & Van........ and also (I think) in Texereau.  
> You must really be looking for a challenge.  I don't really see the 
> benefit of making a R-C that small.  You'll have a big central 
> obstruction and both mirrors will be tough to figure.  Do you have a good 
> flat for figuring the secondary (in the system) or will you be making a 
> test plate or something else?  Why not make a classical Cass. or a 
> Dall-Kirkham?  How about f/15, you will have a smaller obstruction and a 
> little less sensitivity to misalignment.  Of course I've never built one, 
> so what do I know about it :-)
> 
> Peter
> 
> 
> --
>  Peter Hirtle   notpete@scn.org   Seattle, WA.
> 
> 
> 
>