Polarizer Lenses A polarizing filter, used for both color and black-and-white

photography, is colourless and does not affect colour balance, but filters out light with a particular direction of polarisation. This

reduces oblique reflections from non-metallic surfaces, can darken the sky in colour photography, and can saturate the image more by

eliminating unwanted reflections.Polarising filters change the way that your camera sees and treats

light. Particularly – when using one you’ll notice a change in how your camera sees reflections and glare. As a result it also has the

ability to change the vibrancy of some colours in shots.

Where they work best

Water – When shooting a picture of water adjusting your polarising filter will mean you see into the water differently, as they cut out the glare you often get and they can also change the colour of the water.

Sky – Similarly, the color of sky can change remarkably using a polarising filter. Rotating the filter you’ll see a blue sky change from a light pale blue color to a vibrant and deep blue color (depending upon where the sun is). A polarising filter can cut out a lot of the smoggy haze that is often in city shots.

Color – Polarizing filters cut down the reflection that many objects have (even those that you might not think reflect at all). This makes the colours of some of these objects more vibrant. For example, if filming in a garden foliage on trees can be made to look greener than what they would without the filter.

Other Reflections – Shooting through glass can be a real challenge, so shooting using polarising filter can definitely help with cutting down distracting reflections or glare. Similarly photographing shiny objects (like a new car for instance) with a polarising filter will change the way reflections are treated.

Polarisers Change Exposure

One factor to consider with polarising filters is the fact that they can change the exposure needed for a shot. When you see a polarising filter you’ll notice that it looks quite a lot like a sunglasses lens. The filter is dark and works by cutting our some of the aspects of light. As a result less light gets through to your image sensor and it is advised to either use longer shutter speeds, a larger aperture or to increase the ISO setting to account for this. The difference that needs to be accounted for is 1-2 stops. Because of this, it is not advised to use a polarizing lens at night.

How to use

Polariser lens are fairly easy to use. The most common type of lens used is a circular polarising filter, which allows for adjustments of how it impacts the shots, by rotating the front element of the filter. While doing this, the colours and reflections in the shot will begin to change. Continually changing it until you are happy with what can be seen in the shot, and then continue to use the camera normal.

For the best shots, it is advised to try to keep the sun at 90° to the where is being filmed(ie to the side – not at the back and not shooting into the sun). This helps the polarizer to have the greatest effect.

Also, shooting in low light, overcast days or at night with a polarizer is not advisable – it’s like wearing sunglasses indoors and will cut down the amount of light getting through to your image sensor.

Hazards

Polarising filters reduce the amount of light entering your camera, forcing you to use longer exposures. This in turn increases the risk of camera-shake, so when using polarizing filters, always take care to keep your camera steady.

Polarising filters will only have the effect on bright sunny days. If it’s overcast or cloudy, they’ll have little or no effect, so it’s best to remove them. Likewise indoors or at night.

Sometimes polarising filters can make the sky an unrealistic colour. To avoid this, adjust the outer ring for a lesser effect, and also consider taking two shots, one with the polarizer and one without in case you end up preferring the latter.

Varied Results

The extent that polarising filters work varies from situation to situation (often dependant upon the amount of sunlight) so it won’t have a massive impact in all situations – but in some (especially bright sunny days) the impact can be quite staggering.

Example Shots

A ‘normal’ shot taken with out the lens.

The same shot taken using the lens