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Hi Thom,
I see severe vignetting
... would not know where it's coming from but I can give you a clue how to find
the culprit ...
1. Aim the scope at some blue
sky with everything set up as if to shoot a picture.
2. Put the camera on "bulb" and open
the shutter as if you're shooting something.
3. Open the back of the camera (with no
film in it!) ... put your eye at the film plane.
4. Starting from the center, move your
eye to the left and watch either the secondary or the objective ... you will
quickly see what is vignetting as it cuts into your line of sight... repeat for
the other side. Remember to go into the corners ...
There may or may not be a
remedy ... telecompressing pulls the light in at a steeper angle... try
to telecompress behind any off-axis prism or mirror... be aware
that things that normally would not show up in a "straight through" set up
will become painfully obvious if you telecompress.
Good
luck,
Tony
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