Attached Link: http://www.cs.mtu.edu/~shene/DigiCam/User-Guide/950/depth-of-field.html

@Ockham An f-stop is a measure of how wide the aperture of a camera lens is. It is intimately tied up with 2 things; the amount of light that is let into the camera (not really relevant here) and the depth of field (which is). DOF is about how far before and beyond a plane (the focal plane) other objects remain in focus. The above link helps explain depth of field. Just what the exact mathematical relationship is I'm not sure, but I don't think it involves the inverse square rule (at least, not in simple cases:-) but it certainly involves some trig:-))

Hope it helps (result of simple google for "depth of field")

Cheers,
Diolma

Message edited on: 11/21/2004 17:09