Re: [APML] 35 mm Camera & Focuser

["William R. Mattil" <wrmattil@ix.netcom.com>]

Stuart Heggie wrote:

> I sense from what I've read that the most success seems
> to come from people who are putting an eyepiece or loupe on the focus screen
> directly and studying the tightness of the star's image on the matte portion
> of the screen.

I think that more successful Astrophotographers use a knife edge.

> With prime focus, you have no way to lock the
> scope down permanently (unless you never plan to look through it I guess).

Nah that wouldn't work either .... Temperature shift and all.

Build a knife edge into an extra camera body or use a calibrated device
with exactly the same measurements as the camera body you are using.
Hutech is one example of this type of device. 

Regards

Bill

-- 
William R. Mattil	|                              
wrmattil@ix.netcom.com	| http://celestial-images.com      
(972) 399-4106		|
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