The polarizing filter is an excellent add-on to your car camera as it reduces glare and the negative effects of sunlight, that would otherwise lower the quality of the recording, whilst also reducing the overexposure of the sky. Above all, however, it significantly reduces the reflection of the car interior on the windscreen.
The polarising filter eliminates glare by not letting through the light rays perpendicular to the lens. Therefore less light enters from a forward direction and as a result the sky is darker. This makes the CPL filter a highly practical aid when filming or taking photos on a sunny day.