So You Think You Know What An F-Number Is

http://blog.epicedits.com/2007/06/16/so-you-think-you-know-what-an-f-number-is/

So You Think You Know What An F-Number Is

By Brian Auer • June 16th, 2007
Most of us have heard, and probably used, the term f-number. Most of us have also probably used the term interchangeably with “f-stop” or “aperture”. What are all these things, really? Yes, they have to do with the size of the hole allowing light to pass through the lens, and they affect depth of field and light intensity. But I’m talking about what these things really are....

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