You will need all the pixels the camera can produce so set the camera for 1600 x 1200 Fine.
That should produce a good 4 x 6 print.
I can't help with auto/manual as I do not know what they do on that camera.
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I have a JVC GR-DV500U digital camcorder that does stills at 1.33 megapixels. The camera does stills ranging from 1600*1200 down to 640*480; settings range from Fine to Standard/automatic and manual. I would like to know the best resolution for 4x6" prints and/or manual vs automatic. In advance, thanks.

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