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Old 13-09-2009, 03:44 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
But (excuse my non astro logic here) doesn't make sense. It is completely the opposite to terrestial photography. Physics are the same (at least that's how I was taught) - photography and photons are the same at night or day. Sorry, I'm just having a very hard time wrapping my head around it all Peter.

Dave
With camera lenses the aperture can be varied with a constant FL.
So a 'wide open' a lens is operating at its maximim aperture. Not surprisingly it gives its brightest image at this point....hence the amount of flux coming down the pipe, so to speak, is soley (give or take) determined by the aperture. Does that help?
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