That's a huge question, and impossible to give a short answer to....

start here:

http://www.luminous-landscape.com/tu...ries/dof.shtml

then here:

http://www.luminous-landscape.com/tu...exposure.shtml

while you're waiting for these show up after you buy them:

http://www.amazon.com/National-Geogr.../dp/0792274989

http://www.amazon.com/National-Geogr...2733867&sr=1-3

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