All photographers come across a common problem while shooting. That is how to shoot surfaces like water and glass, as they reflect light from the surface and make it difficult to capture the image due to glare. In such situations one needs to know how to use polariser filters, because, unlike other filters, their benefits cannot obtained through image manipulating software during the post- editing process.

Polariser filters help to cut down light entering the camera and reduce the glare from reflecting surfaces. They can be used in coloured, as well as black and white, photography. Polariser filters are made of polarising materials such as Polaroid. Surfaces like water and glass polarise the light linearly after reflection. When this light is passed through a Polaroid, only one component of the polarised light is allowed to pass at a particular angle, thus decreasing the light intensity.

If you see the picture above, the image on the top has been taken with a polariser, thereby reducing the reflection of the surroundings on the glass and allowing us to capture what is seen behind the glass window. In the 2nd image, since there is no polariser, the reflection of the sky and surroundings prevents us from seeing through the glass. Polarising filters, such as the Hama Pol linear 49mm, are also available at a relatively low price. If a polariser filter is rotated at a 90 degree angle, then it would either completely stop the light or let light pass if it was blocked earlier. This filter is usually mounted above the lens and is often also used to increase the contrast and colour saturations if kept at different angles.