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Old February 25th 04, 06:49 AM
David Whysong
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Default ASTRO: CPT18 frame received

In sci.astro.ccd-imaging, Richard Crisp wrote:

In Cass mode, it will be f/12.6 using a 3x multiplier for the
secondary. The illuminated field is 49mm, designed to support either
a 35mm negative or one of the new STL11000 cameras from SBIG.


That's a great idea, but an 18" 'scope with that focal ratio means the
STL11000 pixels subtend only 0.32 arcseconds.

In Newt mode, it will have a focal ratio of f/4.2.


....which is much more reasonable for 9 micron pixels. Why not use
it for imaging in this configuration with a large coma corrector?
Would that work?

Dave

David Whysong
DWhysong (at) physics (dot) ucsb (dot) edu