Polarising Filters
Hints & Tips
Written by Steve Piggott   

For the SLR camera owner there is one simple piece of equipment that can make a huge difference to the images you take. It will give you better, brighter more saturated colours. Can let you see through glass without those annoying reflections. Brings to life shots that include water, improves the look of the sky and, it won’t cost you an arm & a leg. So what is this magical device? Nothing more than a polarizing filter!




How do they work?
Polarising filters a bit like putting blinds on your camera. They will allow light from one direction through but will stop light from other directions. Because light reflected from an object has a different ‘direction’ to the light coming straight from the object a polarizing filter is able to let one direction of light through while blocking the other. As you can easily see the effect the filter is having, it is simply a matter of rotating the front part of the filter until you get the results you want.  The front of some lenses will move (rotate) as the lens focuses. If your lens moves then make sure you focus before you set the polarizing filter otherwise it will move to a different position as the lens focuses.

Circular or linier, which do I use?
There are 2 types of polarizing filters available, ‘linier’ and ‘circular’. While they both achieve the same end result, the way they do it is slightly different. As a general rule, all cameras built in the last 15 years will use circular polarizing filters, linier filters are for use with the older non-auto focus, simple metering cameras. Using a linier on your new camera will not harm it, however it will not give you accurate exposure readings and, can affect the accuracy of the auto focusing. Circular polarizing filters can be used on nearly all cameras, regardless of age.