For optical components with DIELECTRIC coating, there is a polarization dependence to the reflectivity of the incident light when the angle of incidence is not zero degree. So, for mirrors and beamsplitters with dielectric coating, tilted at 45 degrees, the reflectivity is different for parallel and perpendicular (linear) polarized light. In this case, the linear polarizer may fool the light meter. The only way to avoid that is using a circular polarizer. For this reason, you should use circular polarizer in recent Nikon cameras. However, the reflectivity of tilted optical components with METALLIC coating is NOT affected by the polarization of the light. I guess the older models of Nikon Cameras (as F601 and F801) have optical components with METALLIC coating. In that case, it doesn't matter if you use linear or circular polarizer you will get the same results. Best regards Germano Germano Woehl Jr. Sao Jose dos Campos, Sao Paulo BRAZIL e-mail: [EMAIL PROTECTED]
