Re: [ATM] Maksutof corrector minimum thickness

[Daniel Fundo <fundo@bellsouth.net>]

<<  what makes particular glass suitable?
Or in another words, why are ordinary glasses not suitable.  >>

Vladimir,  Light will have to pass through the corrector, therefore,
there can't be any strain in the glass.  It will also have to be clear,
without seeds or mix inconsistancies.  It will have to be edge
supported, so it has to be at least 3/4 inch (19mm) thick.  It will need
to have parallel faces.  All that adds up to a bunch of money.  Why
don't they make big refractors anymore???  Its hard to get a piece of
BK7 that big that would make a good lens/corrector.

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