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Old 31-03-2020, 07:51 PM
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mental4astro (Alexander)
kids+wife+scopes=happyman

mental4astro is offline
 
Join Date: Jun 2008
Location: sydney, australia
Posts: 4,995
Quote:
Originally Posted by gregbradley View Post
Do these CC's allow a removal of a part that allows the above?
As a CC, with VERY long focal lengths...

Make the focal length long enough and the radius of the curved field becomes so long that the field curvature peters out to nearly flat at the illuminated area.

Now at f/3, this is as a Newtonian, so the appropriate coma corrector would need to be used to produce a flat field for photo.

Parks still makes three dual focal length Newt/Cassegrain scopes:

Parks 10" f/4 & f/15 HIT Superior System OTA can be had without mount.

Parks 12.5" f/4 & f/12 HIT Superior System OTA can be had without mount.

Parks 16" f/4 & f/12.5 HIT OTA

Alex.
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