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Cost to refigure..

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#1 JohnMurphyRN

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Posted 23 November 2012 - 10:03 AM

I'm sure we've all seen that 28" Nova mirror for sale, the one with astigmatism and turned edge. What would it cost(rough guess) to have something like that brought up to premium level, or can it be done?

#2 Mirzam

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Posted 23 November 2012 - 12:05 PM

You should probably direct your question to Mike Lockwood or Steve Swayze. The quality of the mirror blank anneal could be a factor. You may be able to get a ballpark estimate, contingent on the glass being acceptable. If the mirror was properly worked and still has astigmatism that is not a good sign.

JimC

#3 kfrederick

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Posted 23 November 2012 - 02:29 PM

The bad edge could be masked off. The astigmatism could from bad glass Or not . Just because someone see astig does not say it has astig . On a test stand if not properly done can show astig on such a big mirror Or improperly mounted in a telescope . James at OMI would who I would check it out .

#4 Mirzam

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Posted 23 November 2012 - 03:22 PM

Very good points. The mirror in question appears to have been used in a rather interesting homemade scope. Was the mirror properly supported? Was the structure warping things out of collimation?

JimC






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