Thread: Solar activity 28 Jan 2019t
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Old 29-01-2019, 11:03 PM
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Merlin66 (Ken)
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Merlin66 is offline 		 
Join Date: Oct 2005
Location: Junortoun Vic
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Thanks guys!
I couldn't afford a commercial CaK scope so I made my own from Omega CaK filters and a Baader Blue CCD filter as an ERF.
Seems to work reasonable well in focal ratios >f20 (I think the optimum is >f30)
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