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Old 28-08-2007, 11:21 AM
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Geoff45 (Geoff)
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Join Date: Jul 2006
Location: Sydney
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Quote:
Originally Posted by iceman View Post
Go to a shorter f/ratio so that you can get the same light in a shorter exposure.
This only applies to extended objects (nebulas, planets etc). Stars are point objects, so f ratio doesn't affect exposure, it just changes the size of the field of view. In fact a longer focal length might be better, because it dims the skylight, since the sky is an extended object.
Geoff
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