At 01:42 PM 8/14/2002 -0400, you wrote: >A studnet asked: > >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? You need to introduce this student to Darkons. They are elements of darkness that are absorbed by lights. Darkons are the real anti-light particals unlike Photons which don't exist. Thanks, Rob -- Rob Miracle Photographic Miracles 203 Carpenter Brook Dr. Apex, NC 27502 http://www.photo-miracles.com