One filter to rule them all
The humble polarising filter is the most versatile and one whose effects can’t be replicated in Photoshop
IF THERE was only one filter on the planet you could ever own, it would have to be a polarising filter because of all the things it can be used for – it’s a filter that can be used for four different effects. Is that even possible? You’ve probably already guessed that it is, and it’s this versatility that makes polarisers essential for all types of photographers. For landscapes, however, you should never leave home without one, especially when shooting water.
Polarising filters are mainly used to reduce surface reflections and glare on water and glass, alongside their ability to deepen blue skies. But they also reduce glare and increase saturation. Moreover, their ability to reduce exposure by up to 1.5 stops means they can be used as a low-strength ND filter. Most of these effects can’t be reproduced in postprocessing. They’re most effective when the sun is at a 90° angle to the camera.
Using polarising filters couldn’t be simpler, whether using them with a drop-in filter system or as a standalone screw-in type. Attach the filter to the lens or holder – some holders have a front attachment for the polariser while others have a recess within the holder itself with dials to turn the filter. Once attached, rotate it until the desired effect can be seen in the viewfinder. Take care when deepening blue skies because over polarisation will leave the sky too blue.
Polarising filters are often used with ND grads and ND filters to combine effects for the best results possible. One thing worth mentioning is that if you’re using screw-in filters and would like to use an ND filter alongside a polariser, make sure the polariser is screwed onto the ND. If you attach the filters the other way around the polariser will rotate while the ND is being attached, which will lose the desired effect. Also, if your lens rotates while focusing it’s best to manually focus and then turn the polariser for the desired effect after.
Even modern cameras struggle to capture scenes the way the eye sees them, and what appears to be a blue sky can be captured white by the camera. Rotating the polarising filter until the sky is blue is all you need to do but take care not to over polarise the sky. Over-polarisation of skies will look unnatural and can also result in areas of the sky being darker than others.
Removing glare and reflections
Glare and reflections on water sometimes make a shot, but in situations where you don’t want them, a polarising filter will be able to reduce or completely remove the glare in many cases. Compose your shot and then simply rotate the polariser until the glare or reflection become invisible. This also works with glass and other surfaces such as car bodywork.
Polarising filters reduce surface reflections and glare, as well as deepen blue skies
Glare: without polariser
Glare: with polariser