Re: ATM DK Secondary Testing and fringe testing

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

Please note that the rings should become more frequent as the distance from
the center is increased with a difference in radius of two surfaces.  Think
about it a moment.
You can calculate how the positioning of the rings should be between the
spherical of a test plate and the parabolic of the secondary.  The other
thing is to make the test plate parabolic and then when you match, the lines
will be straight no matter which way they run.
Bob May
http://nav.to/bobmay
bobmay@nethere.com
NEW! http://bobmay.astronomy.net