In a message dated 8/14/02 20:03:03, PenneP@hsn.net writes: << If a filter has a density of .3 and thus lets through only half of the incident light, would all the light eventually pass through the filter? >> No, or maybe. Leaving aside matters of absorption or reflection (that's why only half makes it through), even if the light were somehow recycled to again attempt to pass through the filter, only half of the remaining light would be able to pass through the filter at any one time, ad infinitum. I don't know what would happen if it came down to the last photon--perhaps it would only pass through half of the time? Are you sure, Andy, that it wasn't an inquiry from someone at stud.net? ;-) Cheers, Rich Mason Photographer-at-Large <A HREF="http://www.richmason.com/";>http://richmason.com</A> See the new section: Rich on the Road
