Your quite wrong of course. Depth of field is that area either side of an OBJECT - in this case it would be the original transparency or negative - within which it is considered to have produced an acceptably sharp image - however you care to define sharpness is not an issue here.
----- Original Message ----- From: "Austin Franklin" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Wednesday, April 17, 2002 8:24 PM Subject: [filmscanners] RE: The"Pepper Grain" problem > Can we now rely on those with an obsession with regard to depth > of field on > Nikon scanners remaining silent on that particular issue? I don't know about that, but I believe using the term "depth of field" with respect to this discussion is erroneous. I posted this once before, but I guess you missed it: As quoted from "Modern Optical Engineering" by Warren Smith, page 156: "The photographic depth of focus The photographic depth of focus is based on the concept that a defocused blur which is smaller than a silver grain in the film emulsion will not be noticeable. This concept also can be applied to a pixel size, for example, a charge coupled device (CCD)." Depth of field, as we know it in photography, is based on a "circle of confusion", which in turn, is based on viewing distance, ability of the eye to discern and the film format. Depth of focus is not based on any of these things and since scanners don't have any "circle of confusion" or "viewing distance", associating depth of field with them seems erroneous. Austin ---------------------------------------------------------------------------- ------------ Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body ---------------------------------------------------------------------------------------- Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body