To: atm{at}shore.net
From: mdholm{at}telerama.com
Reply-To: mdholm{at}telerama.com


I won't quote the previous messages to save bandwidth.  They were both in
the last digest.

Replying to Scott Donaldson:  Your analysis assumes that the surface error
of the diagonal is a smooth curve over the diagonal surface.  That can
happen, but other types of errors are likely too.  For example, a turned
edge on the diagonal would not have any deleterious effect in the middle of
the field for a typical Newtonian setup, but would affect the outer
portions of the field with it's full amplitude.

Replying to Richard Schwartz:
Of course, you are correct.  A relay setup allows a much smaller
illuminated area of the diagonal for a point image.  The diagonal size
becomes nearly equal to the field size.

The whole relay lens idea is one that ATM's should probably look at more.
there might even be an opportunity for commercial products here.

Mark Holm
mdholm{at}telerama.com

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