Urth CPL filters uncovered: Will they work on wide-angle lenses?

You’ll often read that CPL filters don’t work as well on wide-angle lenses. However, Urth CPL filters can be used on wide-angle lenses to great effect.

Polarising filters are generally not used on wide-angle lenses because they’re dependent on the angle of the sun.

The polarising effect is at its maximum when shooting at 90 degrees to the sun. You can easily work out where this is by a commonly-used trick whereby you place your thumb and index finger at an L angle (as if shooting a gun), with your index finger pointing towards the sun, or your light source. The thumb then represents where the polarisation effect is at its most extreme.

When you shoot using a CPL filter on a wide-angle lens, particularly over 28mm, this polarising effect can become uneven. This results in one part of a scene that benefits from the maximum polarisation. But, it means another part of the image gets no polarising effect at all. This effect is most pronounced when shooting blue sky scenes, where you may get a blob in the sky.

Although the uneven polarisation effect on a wide-angle lens might seem undesirable, some photographers actually like the results it creates. So, there’s no harm in experimenting!

CPL filters are also quite thick, as they consist of a double ring. This thickness can affect how images appear when using a wide-angle lens. In particular, if the lens is wider than 24mm, you might notice vignetting when using a CPL filter. Vignetting is when the edges of an image appear darker than its centre. One way to reduce this from happening is to opt for a thin polariser. This will let you still use a CPL filter on a wide-angle lens.

Urth CPL filters come in a thin design so are ideal for use with a wide-angle lens. This avoids any of the annoying problems associated with vignetting. They’re also high quality and durable.