Chuck, I must admit that I was taken back by the size of the secondary. However, after doing the math I think the tradeoffs have been made very well. I look forward to have a peek through the behemoth. It should be a real treat. From: Chuck Hards <chuck.hards@gmail.com> To: Utah Astronomy <utah-astronomy@mailman.xmission.com> Sent: Tuesday, October 29, 2013 3:43 PM Subject: Re: [Utah-astronomy] Journey to the 1.8 meter A 70 inch with a 10 inch secondary in a Newtonian configuration would have to be of similar f-ratio, f/8-ish, or over 45 feet long with the eyepiece somewhere near 40 feet. Again, a too-tall ladder and probably unstable in any kind of breeze at all. On Tue, Oct 29, 2013 at 2:45 PM, Erik Hansen <erikhansen@thebluezone.net>wrote:
Or how about a 70 inch f4 with a 10 inch secondary.
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