What is an F/Stop?
Ever wonder what an f/stop is, well http://en.wikipedia.org/wiki/F-number has a great explanation. This is essentially a way to express how wide open a lense is in a camera. It is a pretty simple idea. An F-number or F-stop or aperture setting of F/1 means that for a 77mm lense (as on my big Canon lenses), the thing is all the way open and lets in lights across the entire 77mm width. Similarly F/2 means that the lense is half open so lets in 77/2. Now in a camera, every decrease of aperture
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