I won't build it by myself. I will either have Steve build it or maybe I should take one of your classes. I have only built one mirror and a mirror that size (20") needs someone around with lots of experience.
 
A 20" mirror at f5.5 will yield a 2794mm focal length.  That should yeild 90x with the 31mm I have and 798x with a 3.5mm (maximum useful magnification) eyepiece.  I sent off a message to AstroSystems and asked them how much a 20" & 22" mirror and mirror cell would weigh. I think I am liking the 20" the more I think about it.
 
Jim
-----Original Message-----
From: John.Zeigler@FranklinCovey.com [mailto:John.Zeigler@FranklinCovey.com]
Sent: Wednesday, October 01, 2003 3:02 PM
To: uvaa@mailman.xmission.com
Subject: RE: [UVAA] Scope Length

Jim, that sounds like a good point to design around.  Long enough F# to avoid most of the off axis aberations, short enough you do not have to climb too high on the ladder.  It will still take up a fair amount of room for transportation though.
 
Do you plan on making the mirror yourself, or have Steve build it?
 
John Zeigler
 
 
-----Original Message-----
From: Gibson, Jim [mailto:gibson@dpg.army.mil]
Sent: Wednesday, October 01, 2003 2:57 PM
To: 'Utah Valley Astronomy Association'
Subject: RE: [UVAA] Scope Length

John
for 110" I could go for a 20" mirror with a f5.5 ratio.  That might be the best compromise.
Thanks
Jim