Thread: Barlow, Powermate advice
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Old 01-10-2017, 06:34 PM
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Merlin66 (Ken)
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Merlin66 is offline 		 
Join Date: Oct 2005
Location: Junortoun Vic
Posts: 8,907
David,
The optimum f ratio for detailed planetary/ solar is from f25 to f30.
The PM/ barlow should bring you close to these numbers.
Nothing to be gained from 2” fittings, the target image is so low.
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