Re: A spherical 4.5" mirror at f/10. Is there any reason not to make something like this off-axis and eliminate any obstruction. No fancy mirrors or anything like that since it's spherical right? Heck, why not get a couple of flats and fold it? I picked up a 4.5" (maybe just 4") blank at TSP for $1. Could be the best dollar I ever spent.
Donovan
> -----Original Message-----
> From: staringinto@space.com [mailto:staringinto@space.com]
> Sent: Wednesday, July 11, 2001 2:40 PM
> To: atm@shore.net
> Subject: ATM 2nd post - first scope : )
>
>
>
> I did not mention the focal length of the mirror in my first
> post. If I remember correctly (correct me if I'm wrong)
> spherical mirrors are generally f/10.
>
> I hadn't thought about the observing height of the eyepiece,
> so I'm glad that issue was raised. I had planned on using an
> adjustable stool and observing from the seated position. Is
> standing preferred/more comfortable?
>
> Also, if anyone can tell me which box I packed the 4-1/4"
> mirror and diagonal in the last time I moved, I'd greatly
> appreciate it! :) :(
>
> Darren Addy
> Web Specialist
> University of Nebraska at Kearney
>
>
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