What is “Hyperfocal Distance”?

Question

I'd like a clear & easy-to-understand (especially for non-physics-types) explanation of what Hyperfocal Distance is, how it affects photographs, and what determines its value.

Answer

The hyperfocal distance is the distance at which everything from 1/2 the distance to infinity is in focus.

For instance, if the hyperfocal distance of a particular lens at a particular aperture is 100ft, then by focusing at 100 ft you can capture anything from 50ft-infinity in clear focus.

A more in depth explanation can be found at www.dofmaster.com

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