Re: [ATM] Re: How fast is too fast?

[Daniel Fundo <fundo@bellsouth.net>]

The easiest way to solve the diagonal problem in a short f/ratio
Newtonian would be to use a transfer lens.  The only problems are
getting well corrected lenses for the assembly and, with the
introduction of refractive elements, chromatic aberration.

The other solution would be to go with a Mersenne arrangement.  In a
Mersenne, the f/ratio of the final focusing element is the f/ratio of
the system.  In a small telescope, a camera telephoto lens might work,
but at lower ratios (<f/4) getting the light cone into the eyepiece
would be a bear!

*****-----
Dan F.
Secretary/MAS
Memphis, TN
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