The Singh-Ray LB Warming Circular Polarizer is the next bold and innovative step in Singh-Ray's development of polarizing filters. This filter has increased its light transmission capacity by 60% - no small endeavor. Basically, they're talking about a 2/3 stop increase in brightness.
This filter also has a warming element to it which can help when it is either overcast or if you're shooting in open shade.
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! Circular polarizers are specifically designed for use with auto-focus SLR cameras (They will also work on manual systems and video cameras without problems)
77mm LB Warming Circular Polarizer (Thin Mount)
Storage Case with Liner
Warranted Against Manufacturer's Defects for 90-Days