From: "CSC" 
To: "Atm" 
Reply-To: "CSC" 


All BK7 is not created equal.  If I may quote my friend Stanley Brower of
Laboratory Optical (ret), from one of his notebooks:

"This is the worst piece of junk glass I ever got from Schott. 
Supposed to be BK7 Grade A"

The mangins are double pass so the glass needs to be super good. Do the
melt numbers match?  Same melt?  I heard this is an advantage.  Hearsay
only. Colin

-----Original Message-----
From: owner-atm{at}shore.net [mailto:owner-atm{at}shore.net]On Behalf Of Ellen
Mackenzie
Sent: Tuesday, December 03, 2002 12:03 AM To: atm{at}shore.net
Subject: ATM Schupmann Design



Does anybody have  more than what is shown on the Stellafane site on the
Schupmann telescope. The article by Scott Milligan refers to what may be
deliberately left-out dimensions, radii etc. He refers to Jim Daley's
booklet and ATM Mike Mattei. I am in love with this instrument for two
reasons, one, I can lay my hands on all the one inch BK7 I want at no
charge, and two I hate the diffraction patterns from obscured light trains.
Hal at mackenzieconsulting{at}sympatico.ca

--- BBBS/NT v4.00 MP