Re: Cheap imaging?


"Rich" <> wrote

I had an 8" f3 once. I tried it out after using mostly
SCTs. The coma was horrific.

I wonder how well Televue's new coma reducer lens would work with such a low
F-ratio? The new Televue product is designed to screw into the nose of an
SBIG STL-11k CCD camera, but is should work with any camera.

My friend Alan Chen had such success with putting a starlight xpress CCD in
place of the secondary mirror in a inexpensive home-made 10-inch F/5 Newt
that he told me he was going to get a Royce 12.5-in F/5 mirror to make a
bigger and better one. I'm not sure how he made out with that project. I
know of another guy who has had success with doing the same thing with an
Obsession 25. He had to add an Optec field de-rotator since the scope has an
alt/az drive. Even with the camera and de-rotator mounted on 'fins' right in
the center of the optical tube he got some very nice images.

George N


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