Re: ATM Star Testing

[epabcc@epa.ericsson.se (Bratislav Curcic)]

Stephen Tonkin wrote :

>> "Robert  C. Pfaff" <PFAFF2@delphi.com> wrote:
>> to test a corrected
>> mirror like a star test you need a collimating lens or mirror  to get
>> parallel light. It should be as large as the mirror being tested.
> 
> <PEDANTIC>
> Forgive my pickiness, but I think that last sentence would be better as
> "...should be at least as large ..." to avoid it being misinterpreted to
> mean "... exactly as large ..."
> </PEDANTIC>

< ultra pedantic >

Forgive my pickiness too, but you don't need a parallel light nor you
need a lens "at least as large" to null test (or star test, if you wish
to call it that way) your mirror. See Dall, Ross, Offner, Waineo... 
etc tests.

Bratislav