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Re: [ATM] Lens after diagonal?



There is a scope design called a Johnsonian that is for all wants 
and purposes a bent Gregorian.  The secondary of the primary 
mirror is a very small, 3/4 inch or less, diagonal flat.  The airy disk 
from this secondary is picked up by a second elipsoid primary that 
then sends the image to the eyepiece.  A good amount of 
amplification can be realized, but you could also treat it as a mirror 
based relay system.  It would be an odd duck, but it would work.  
Kind of looks like a T.

David Davis
Toledo, OR  97391
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