Re: [ATM] first light on a Lurie-Houghton

["Bob May" <rmay@nethere.com>]

You're sort of indicating that it is coma that is your problem.
This would be the same ias if the Newt parabola was tilted in the
tube.  The lenses wouldn't contribute to that very much but the
angle of the primary, which is a spherical surface would.  As a
result of this thinking, I'd adjust the primary tilt to see if
the coma goes away.  Consider that the coma is pointing towards
the center like any parabola would and adjust accordingly.
The last resort is to put the lenses up on a stand with a flat
(or is it a spherical) mirror behind and terst for concenctricty
of the image with the foucault test.  You will need to have a
coaxial light with this test as any offset of the light source to
the reurned image will produce all kinds of interesting effects.
his means a beamsplitter to get things together correctly.
Good luck and I hope this thought help0s!
Bob May

rmay at nethere.com
http: slash /nav.to slash bobmay
http: slash /bobmay dot astronomy.net


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