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Old 09-08-2009, 10:28 AM
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Mike21 (Michael)
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Different, but related.

Quote:
Originally Posted by Kirkus View Post
Ohhhh. OK. So I shouldn't be interchanging the terms "aperture" and "F Ratio", because they are actually different things.


Very interesting stuff (my family and friends might argue that point).

Different but related. The f-ratio is the aperture per focal length. A fast f-ratio has big light collection capacity and by comparison does not try to magnify too much. A slow focal ratio, the opposite.

This explanation may sound whacky but it initally helped me. Photography is analagous to making cordial. If cordial was aperture and focal length water. A fast ratio is like concentrated cordial in a small amount of water, you don't need to taste much before you've had enough; fast exposure. Whereas a slow f-ratio is like a drop of cordial diluted to buggery, you'll need to drink heaps before you can even work out what flavour it is.
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