Re: Cassigrain Binoculars

Bob Bond (rgb@ncube.com)
Tue, 18 Apr 1995 09:51:15 +0800

Why would a mirror chopped in half be better than a binocular viewer on a single mirror? I can about imagine the diffraction rings and trying to star-test each half into collimation... Chopping a mirror in half can't be good for its figure either. Of course my father-in-law *does* have a rock saw :-).

Bob Bond

From: rhill@LPL.Arizona.EDU (Rik Hill) >Subject: Re: Cassigrain Binoculars
>
>> There was a good description in S & T in the 70's of a 6"F15 Cassegrain
>> binocular, on a massive equatorial mount. The whole instrument weighed
>> about 600 lbs ! It looked like a collimation nightmare....
>
>There was also an article in an old S&T from the 1960's or maybe
>older where some fellow cut an 18" mirror in half to make huge
>Gregorian binoculars. I have been unable to locate the specific
>reference.-Rik
>