Re: [ATM] A bit of hand polishing advice please................

["John and Bernadine Murray" <onslow@cyberone.com.au>]

G'day John,
	All the foucault images are with a stellafane type tester (moving
source) with the knife edge coming in from the left. Knife approaching from
the left and the diffraction ring on the right, does this indicate turned
down or up edge? I'm working on the assumption that it's turned down
although it wouldn't be the first time I've been wrong ;-)


Cheers


John

-----Original Message-----
From: John Lynch [mailto:john_lynch2006@yahoo.com]
Sent: Wednesday, 22 November 2006 10:04 AM
To: John and Bernadine Murray
Subject: Re: [ATM] A bit of hand polishing advice please................

John,

For a spherical mirror with no turned down edge, you should see the
diffraction ring around the entire mirror's perimeter.  In Foucault.jpg
(#3), the ring is visible on the right-hand side.  I assume your light
source is on the left-hand side.

John Lynch

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