The reduces light entering the lens that is oriented in a single plane (polarized light) without affecting color temperature. Light reflected off glass or water, as well as some of the light emitted from the sky on a clear day, is polarized.
When It rotated to the appropriate angle, Cavision 4×4 can largely eliminate reflections off glass or water. Furthermore, it will reduce glare and excess sky light, thereby increasing sharpness, contrast and color saturation of the image. It does not cause interference with the lens’ auto sensors. If using the auto sensor functions on a lens, this filter type is recommended.