Re: [ATM] very long focus objective

["Bob May" <bobmay@nethere.com>]

Ah, I didn't even go so far as to notice the huge diameter of the first
lens.  Is that really a 5" or so or is it really a 27" lens?  If the first
lens needs to be that large then it will be collecting light from that much
area (or a significant amount considering that the FOV will be a fraction of
a degree for a real world application) and thus be considered to be a 27"
lens.
I'll note that putting any lens up on a flagpole, the problem will be the
sway of the pole, not the rotation problems of the pole so the objective
would be waving about up there pointing at different locations as it does
so.  That could make some people motion sick if they don't watch it,
especially if the scope is on an upper floor which can be a fairly moving
thing to begin with.
Bob May
http://nav.to/bobmay
bobmay@nethere.com
NEW! http://bobmay.astronomy.net


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