Quote:
Originally Posted by noswonky
The SDM scope isn't a particularly short focal length - it's f/5, but with a folded light path - three mirrors with the eyepiece half way up the tube instead of at the top.
However, the SDM site says on the prices page:
"The Compact scope is no longer made or offered. All scopes are classic style only."
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Thanks Peter. Yes I recognise that this particular scope is a folded design. The Compact scope that SDM no longer makes is of the style of SDM#024.
I'm interested in the short focal length mirrors. SDM has already used a few shorter fl mirrors - eg. SDM#s 18, 22, 36. Check SDM#036 - 22", yet feet on the ground (almost, "tippy-toe"!)).
Check the Starmaster scopes using Mike Lockwood's mirrors down to f3.3.
http://www.starmastertelescopes.com/
Mike has also demonstrated a 20" f3 scope.
http://www.starmastertelescopes.com/MX20.htm
....and a 14.5" f2.55!
http://www.loptics.com/fast14p5.html