Say you want short depth of field (open aperture, gathering more light) but you are in bright sunlight... adjust with shutter speed.

f/3.2
Shutter 1:1600
Iso 250

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[Bleeeeep!], the cup of ignorance in this thread overfloweth . . . Salmo g
Truth be told, I've always been a fan of the Beavs. -Dan S.