In a message dated 3/15/05 9:58:48 PM, tillerman1@videotron.ca writes:
Why put the camera inside?
Why not a diagonal followed by a relay lens/ field flattener combo? the
direction of focal plane curvature would then be the same as a regular
newtonian
No heat build up or cables inside the tube and the face of the camera
body could be mounted just proud of the tube where the film loader
opening is presently located.
And the central obstruction would be no greater than it is currently.
Just a thought...
Too bad Roland isn't on the list anymore, I'm sure he could shoot this
concept full of holes in a heartbeat. :^)
George Anderson
George:
Schmidt cameras have very fast focal ratios; ie. f1.5, f1.65, f2.0, f2.2 and their light cones are very steep, fat or whatever term applies. Any secondary would have to be very large to get the focal plane outside the tube and be accessible. The Tak Epsilon's do manage this but they are more like f3.3 and still have very large secondaries. I'm not saying large secondaries are a problem for imaging, because they are not, but a secondary for an 8 inch f1.5 Scmidt would probably be 5 inches in diameter.
Kent Kirkley
_______________________________________________
Astro-Photo mailing list
Astro-Photo@seds.org
http://seds.org/mailman/listinfo/astro-photo