Thread: Parabolic mirror for photography
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Old 18-03-2009, 06:51 PM
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Geoff45 (Geoff)
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Join Date: Jul 2006
Location: Sydney
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For a 6" you need about f9 for a spherical mirror to be acceptable, as long as you're not too picky. With a 5", you wouldn't go shorter than f8.
Geoff
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