From: Jon Bishop 
To: 'Jean-Guy Moreau ' , 'ATM '

Reply-To: Jon Bishop 


Hi,

Thanks for the info - I will give it a try.

I am also using a slitless tester. In other words the led is half covered
with a knife edge (actually a utility knive blade) and I use the same blade
to cut the returning rays.

I have been polishing for over 4 hours. I still see some pits so I am
planning at least a couple of more hours of polishing. Of course it is way
too early to be testing under the knife, but I thought it would be
interesting to see. The mirror is very reflective at this time so I don't
think that is the problem.

Maybe my led is way too dim. What light source are you using?

Jon

-----Original Message-----
From: Jean-Guy Moreau
To: Jon Bishop; ATM
Sent: 8/14/03 5:36 PM
Subject: Re: ATM Foucaul pictures using digital camera.

Hello Jon, i have exactly the same camera and have no problem taking
pictures of Foucault test. Autofocus works great. You must use the optical
and digital zoom at maximum, asa 400, and full auto everything else. How
long have you been polishing so far? Maybe you simply have not enough light
at this stage of polishing? I am using a slitless tester, it has more light
than a pinhole one, what are you using ?

Jean-Guy




 in the process of polishing and figuring an 8" F5.25 mirror. I would
like some advice on figuring it, but before I do that it would be nice to
take some pictures of the mirror under test.

I have a Canon A40 digital camera, but when I try to use it it does not
pick up the mirror disk. Has anyone suceeded in using an autofocus digital
camera to do this?


Thanks,


Jon Bishop

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