Re: Rayleigh Water Test (Was: Re: [ATM] 30" Flats)

[Andy Saulietis <iss@pvtnetworks.net>]

Re fluid flats:

An old friend of mine in TX used a mercury flat covered with oil
to get both high reflectivity and ripple damping for testing
a 10" S-C that he made the optics for. This was about 35 years ago,
he said he tested at 3am to minimize traffic induced vibrations.

There was a hole in the center of the 'flat' for testing at autocollimation
focus for the primary; the system was tested at the cass focus above the
scope.

Strictly speaking, a fluid 'flat' will have a ROC equal to the
radius of the earth..not a problem until your aperture is several
meters.


Andy Saulietis
ISS Enterprises
10 Milky Way
Mayhill NM 88339


World's first astronomy land development:

http://www.pvtnetworks.net/~iss/starend1.htm

15 of 17 lots sold to astronomers as of 2/08/05

505-687-3067 voice/fax, call voice or e-mail to set up
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