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Old 13-09-2009, 01:45 PM
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Peter Ward
Galaxy hitchhiking guide

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Join Date: Dec 2007
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Quote:
Originally Posted by dpastern View Post
....

edit: so a f3 10" newt will gather light twice as fast as one that is one stop slower in terms of f ratio (but same aperture, i.e 10").
No it won't. Sure we've been haggling over details in the limit cases, but
a 10" is a 10" you will only get a marginal performance increase (using a CCD) with a faster system.
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