Thread: Can you use an H-alpha filter behind a Baader solar film filter?
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Old 08-07-2010, 01:04 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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Yes,
gets expensive!
The F-P elements have to be much better than 1/15 to 1/20 wave flatness and held together, while "tuning", to be parallel within sub micron tolerances. Certainly not your average filter!!!!
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