What Is a Polarizing Filter and How Is It Useful?

Polarizing filters are useful for both color and black-and-white photography.

A polarizing filter is a handy photography accessory that can be used with both film and digital cameras. The filter is used to reduce or eliminate glare, increase overall saturation, and darken blue skies in photographs.

Identification

The most common polarizing filter is a circular, gray, glass filter made with two rims. The inside rim attaches the filter to your lens. Once attached, you can rotate the outside rim to gain the desired saturation, darkened sky, or reduced reflection effect.

Functions

A polarizing filter can be used to reduce reflections and glare on smooth surfaces such as glass, plastic, and water. These filters also increase overall color saturation, the intensity of the colors in your photograph, and can darken blue skies in both color and black-and-white pictures.

Considerations

Although a polarizing filter is used to reduce glare and reflections, it does not completely eliminate direct reflections such as in mirrors or on bare metal surfaces. "The reflective angle of the subject's surface is also critical, with the filter's maximum effect occurring when you photograph a subject at an oblique angle (about 35 degrees to the primary plane of the surface of the object)," explain Henry Horenstein and Russell Hart in the book "Photography."

References

• "Photography"; Henry Horenstein and Russell Hart; 2004