Thread: which barlow for planetary
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Old 24-02-2013, 12:53 PM
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asimov (John)
Planet photographer

asimov is offline 		 
Join Date: May 2005
Location: Bundaberg
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With a 100mm's of extension tube, a 2X Barlow will turn into a 3X barlow - You can now obviously do the math & have any length extensions to get almost any FR above F20.
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