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When putting the big (14-inch diameter or so) polarizing filters over your lights when copying, be sure that all other extraneous light that is NOT passing through the filters does not hit the ceiling or walls of the room where you are copying. This extra light can and will create unwanted light sources on your subject. I always used Kodak's old copy light set-up which had specially-constructed bowl-shaped housings that shielded this unwanted light from striking the walls, ceiling, etc., and which allowed only the polarized light to "escape" onto the surface of the subject being copied. Set up your lights at approximately 45-degree angles to the subject plane (adjust as necessary), and simply rotate the big filters until the reflections are removed as much as possible from the subject (as viewed through the copy camera). Then rotate the camera's polarizing filter 90-degrees opposite to the filters on the lights until ALL of the reflections have disappeared. You do not have to measure the angles of the filters--you can see the reflections disappear yourself as you rotate the filters. Take a meter reading at the subject plane--a gray card with TTL metering works well and requires no compensation or other calculations. With hand-held meters, read the light at the subject plane, and then open the exposure by 1-1/3 f-stops for the camera's pola filter, as the meter will read the loss of illumination from the polarizing filters being used over the lights. This method is particularly valuable if you are copying subjects with highly reflective surfaces (such as b&w glossy prints), or oil paintings with their brush strokes and globs of hardened paint which REALLY reflect the copy lights without pola filters. Copy stands are very convenient for quickly copying many small subjects, but are not an absolute necessity. Just be sure to "square" the camera to the subject, cover the tripod legs with black cloth to prevent metallic reflections, and keep your own reflection out of the scene with a long cable or electronic release to the camera. Shoot some test film beforehand, and you probably will not need to bracket if you increase and decrease the exposure according to the brightness of the subject as in any other photo. The important thing is to cover the light source with polarizing filters, not just use a pola filter on the camera. There is a huge difference. Hope this helps, Mike, and any other potential photo copiers out there! John B. Corns Owings Mills, Maryland _____________________________________________________________________ You don't need to buy Internet access to use free Internet e-mail. Get completely free e-mail from Juno at http://www.juno.com Or call Juno at (800) 654-JUNO [654-5866] ======================================================= -> SPORRS: 'Serious Photographers Of Railroad Related Subjects' -> Web Site: http://www.anet-stl.com/acphotog/sporrs/ -> Message © 1998 SPORRS® - All Rights Reserved =======================================================
