[ATM] A ronchi question

[Don D'Egidio]

I think the Mobsby Null test is not recommend for optics faster than F/7.

Don

----- Original Message ----- 
From: "Guy Brandenburg" <gfbrandenburg at yahoo.com>
To: "hermit" <hermit at outofoptions.org>
Cc: <atm at atmlist.net>
Sent: Wednesday, March 09, 2011 6:22 PM
Subject: Re: [ATM] A ronchi question


> Yes. A Mobsby null test was invented which does exactly that. WillBell sells it. However I could 
> never get it to work.
>
> Sent from my iPhone
>