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Old March 4th 04, 05:15 AM
Lawrence Sayre
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Default Null test lens for a 30" F/4 mirror?

On Thu, 04 Mar 2004 04:13:37 +0000, Richard F.L.R. Snashall
wrote:



Lawrence Sayre wrote:

What size, quality, and specific type of lens would be required to use
a Foucault tester as a Ross Null Tester for a 30" ~f/4 mirror? Does
anyone make such a beast?


You may find there are multiple answers to this question. For example
(if you
have OSLO available to you):

http://users.rcn.com/rflrs/Ross_Test.len


Lawrence Sayre




Sorry, but I'm exclusively a Linux OS person. Can't run most Windows
stuff.

Lawrence Sayre
--
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My philosophy, in essence, is the concept of man as
a moral being, with his own happiness as the moral
purpose of his life, with productive achievement as
his noblest activity, and reason as his only absolute.

Ayn Rand (in the appendix to 'Atlas Shrugged')
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