Schneider 4x5.65" One-Stop Polarizing Glass Filter - While the standard Schneider True-Pol is 1-3/5 stops, the Schneider One Stop Linear Polarizer significantly reduces reflections while reducing available light by just one stop.
Light rays which are reflected become polarized. Polarizing filters are used to select which light rays enter your camera lens. They can remove unwanted reflections from non-metallic surfaces such as water or glass and also saturate colors providing better contrast. The effect can be seen through the viewfinder and changed by rotating the filter. The filter factor varies according to how the filter is rotated and its orientation to the sun.
Note! Linear polarizers are used with most video and manual focus photo cameras. They are not recommended for auto-focus SLR cameras.
4x5.65" One-Stop Water White Linear Polarizing Glass Filter