hi tnott and rmcconachy,
Thanks for the links, it looks like a lot of good info! The stellafane site is huge!
At the moment I'm really interested in Tim Nott's design...his 16" is beautiful....
http://www.iceinspace.com.au/index.p...63,324,0,0,1,0
There are a lot of designs out there, so I'm just trying to look around, see what I like and get my head around what the basics are...at the moment I'm basing my thoughts around a 16" f4.5....I think this would put the eyepiece at a reachable height at zenith...