Checklist: Using polarizing filters

1: Buy a circular polarizing filter which matches the thread on your lens; check the end of the barrel to find out the correct size. Canon’s 18-55mm and the Olympus 14-42mm kit lenses have a filter thread of 58mm. The Nikkor and Pentax 18-55mm kit lenses have a filter thread of 52mm. Sony’s 18-70mm kit lens has a 55mm thread.

2: With the polarizer screwed onto the end of your lens, turn the outer section to see the polarizing effect. As you turn it, the effect will increase and decrease, then repeat. Simply stop when it looks best to you. The strength of the effect also varies depending on your angle to the Sun.

3: To prevent your DSLR from counteracting the polarizing effect, set the White Balance to Daylight and consider applying negative Exposure Compensation of, say, -2/3 or -1 EV.

4: After taking your photo, remember to set the White Balance back to Auto and the Exposure Compensation back to zero. Unless it’s a bright sunny day, remove the polarizer and return it to its case.

Watch out!

Polarizing 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.

Polarizing filters will only have the effect shown here 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 polarizing 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.

Cheaper kit lenses rotate their barrels when auto-focusing, which will also turn a polarizing filter, changing its effect. If you have this kind of lens, half press the shutter release first to autofocus before turning the polarizer. When subsequently turning the filter, you may knock the focus very slightly, so once the polarizer is in the right position, half-press the shutter again to get the focus spot-on.

Equipment tip

Polarizers come in two main types: Linear and Circular. Circular polarizers, or CPLs for short, are designed to not confuse the autofocus or metering systems on modern cameras, so this is the type you’ll need to buy for your DSLR.

Hoya is one of the most respected filter brands, and if you can afford it, go for one of its 'HMC' Multi-Coated models for better quality. See left for prices of Hoya Circular polarizers.

Polarizing filters are quite thick and can sometimes darken the corners of ultra wide angle lenses. To avoid this, buy a thinner polarizing filter.

Any questions?

If you have any questions about using polarizing filters, or would like to show us your own photos taken with polarizers, please post them in the dedicated section in the Cameralabs forums.