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Old 07-06-2023, 09:19 PM
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David Fitz-Henr
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David Fitz-Henr is offline
 
Join Date: Aug 2007
Location: Bowen Mountain
Posts: 837
Quote:
Originally Posted by alpal View Post
Great image David,
it's really sharp - you must have had good seeing
and you've gone deep with heaps of background galaxies.

Could you please tell us more details about that replacement mirror?
What type is it - a conical? and what is the f number?
Do you have any photos of the "Bunyip 12.5" Newtonian Astrograph -
inside and out?

cheers
Allan
Thanks Allan.
It is a conical mirror that I purchased from R.F. Royce to replace the original conical mirror that developed a crack and ruined the figure. It is f/5.05 natively, but I am using a 3" Paracorr that changes it to an effective f/5.8. I have pictures of its construction here: https://pbase.com/david_fitz_henry/317_5mm_astrograph
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