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Re: Newtonian Astigmatism

Started by m87, 10/02/2003 07:39PM
Posted 10/02/2003 07:39PM Opening Post
Check if one axis of the astigmatism pattern
lines up closely with the long axis of the tube
(long axis as you look in the eyepiece).
I have often seen this situation when there is
too much wadding in the secondary holder. The
pressure causes the secondary to bow outward,
which leads to astigmatism.
Posted 10/02/2003 08:01PM #1
Thanks for the input! Can you tell me what defect in the mirror actually would cause astigmatism?