Re: [APML] 48 Inch Schmidt Telescopes

[Mark Kaye <mark.kaye@sympatico.ca>]

>Oh, I just found the web page.
>
><http://www.cs.toronto.edu/~wayne/schmidt/>

    Hmm, it looks exactly like our club's 60 cm Schmidt and the specs on 
the web page are all the same except for the aperture.  Think about 
it.  Put a 20 by 25 cm film holder in a 30 cm aperture scope and you do not 
have a lot of room left over to take in any light.
    This beast is a dinosaur.  It uses thermionic valves, for heaven 
sakes.  The curve of the film holder is so severe that you have to bake 
(yes, I said bake) under pressure and cut the film onto the film holder to 
get it to take the proper shape.  Try that with your specially hypered 
film.  The logistics of using this camera are so difficult that it never 
ever gets used.  It is literally the size of a VW bug, about as pretty and 
twice as heavy.  It used film that is not available any longer and getting 
suitable film for it today would be very difficult.  I would think long and 
very hard about using this camera before buying or transporting it.
    Then you have to think about the images that it produces.  The image 
scale is so small that while covering a lot of sky, very few actual deep 
sky objects will show on the picture.  It was designed to take meteor 
photographs at f0.85.  I have seen images from the camera and they are 
scratchy old things, the way you have to abuse the film to take a picture 
precludes a clean negative.
    Sorry to burst anyone's bubble, but this is hardly a practical camera 
for anyone other than a museum.
    Clear skies!
                MK

http://www3.sympatico.ca/mark.kaye/


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