Light rays which are reflected by any surface can become polarised and so polarising filters are used to select which light rays enter your camara lens.
• They allow you to remove unwanted reflections from non-metallic surfaces such as water, glass etc.
• They also saturate colors and increase contrast. This effect is often used to increase the contrast and saturation in blue skies and white clouds
• Hoya's Polarizing filters do not affect the overall color balance of a shot
There is a tendency for images seen through the viewfinder when using a Polarizer filter, to appear more blue or brown than they turn out in the photo. Hoya has corrected this with the Wide Band Circular Polarizer Filters.