[Author Prev][Author Next][Thread Prev][Thread Next][Author Index][Thread Index]

Re: [ATM] Am I there yet?

At 2004-09-08 14:52 -0700, Don Bates wrote:

>2) TEX shows the figure to be just OUTSIDE the tornado
>on the ML graph. How can this be when it is almost 2
>times better than the Raleigh criteria?

Forget the ML graph - it only says where to work a mirror (with careful 
interpretation); it's worthless as an evaluator because it ignores an 
error's area.

>3) FIGURE says that the mirror is 1/9.54 P-V, with a
>Strehl of 0.953.

Sixtests agrees with FIGURE - surface RMS 10.8±3.6 nm (2 sigma, assuming 
.005" reading accuracy) = .941 Strehl.

>5) If I try to improve this mirror, am I just asking
>for trouble?
>TEXEREAU MIRROR TEST SHEET
>...

Strehl .941 is certainly good enough to say "It's DONE!".  If you really 
want to ask for trouble, the best-fit conic b = -.890, undercorrected, so 
use some more parabolizing strokes.  But with both feet already in the 
promised land, max 1 min spells between testing.

         -- Jim Burrows
         -- mailto://burrjaw@earthlink.net
         -- http://home.earthlink.net/~burrjaw
         -- Seattle N47.4723 W122.3662 (WGS84)  

_______________________________________________
ATM mailing list http://www.atmlist.net/