digital camera capabilities / was Re: 1000+ old computer in Canada, for sale

Bob Bradlee wrote: The idea that the (optical) zoom matters, presumably because people think that more zoom means getting further away and changing the viewpoint and therefore means greater depth of field[1], is actually a fallacy. For any given width of view of a subject (in other words, getting the same amount in the frame), using a given aperture, the depth of field is the same regardless of the focal length of the lens.It may seem counter-intuitive but it's because the depth of field and the aperture both are related to the focal length. Anyone who doesn't believe this is welcome to check the equations in any standard textbook such as LP Clerc's "Photography" :-) Of course, changing viewpoint does make a difference to the perspective in the view. 1] This is the correct term for what many people wrongly call depth of focus. Depth of focus is something different, internal to the camera. -- Pete Peter Turnbull Network Manager University of York