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Old 16-02-2012, 04:40 PM
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tilbrook@rbe.ne (Justin Tilbrook)
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Join Date: Jun 2007
Location: Penwortham
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8" F/4 atsrograph advice needed.

Hi,
I would like to get some opinions on possible problems with my 8' f/4 astrograph.
It's a standard off the shelf BINTEL job, runnung on a HEQ 5 pro mount.
When I recieved the scope I collimated with my laser, seemed slightly off so corrected that.
I'm using a 2" coma corrector, again BINTEL stamped, don't the real identity of it.
The image below was taken using my canon 1100D, and focused with a bahtinov mask.
As you can see the star images to the left of field are not good. I was wondering if this is.
A. Collimation problem.
B. Coma corrector not quite up to sctrach.
C. Poor mirror.
I think C is unlikely, because it showed good figure in star testing.
Any suggestions?
Advice would be appreciated.
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