UV and CPL filters don’t perform the same task. So, whether you choose a UV or CPL filter largely depends on what you want to achieve from your photography. Most photographers, especially those shooting outdoors, use both filters at different times, although they can even be used simultaneously.
Both UV and CPL filters protect a camera lens. However, a UV filter is mainly used for protective purposes only.
Modern digital cameras block out UV light from a lens. So, unless you’ve got an old camera, most times you’ll use this filter simply to protect your lens. When you’re out and about, dust, dirt, sand, grease, moisture and finger marks can all get on a lens. Therefore, keeping a UV filter on lets it bear the brunt of these unwanted contaminants, ensuring your lens remains untouched. In particular, if your UV filter suffers from scratches or knocks, you’ll need a new one. A UV filter is cheaper to replace than a camera lens. For these reasons, many photographers choose to leave a UV filter on their camera lens at all times.
A UV filter isn’t normally used to improve the quality of an image. Interestingly, comparison studies show that this lens doesn’t have any adverse impact on a photo if left on the lens. However, a UV filter can sometimes eliminate a blue cast that occurs when it’s very bright or at high altitude.
Most photographers wouldn’t leave a CPL filter on their camera all the time, especially for lens protection. But, if they need to alter a scene’s colour balance, this is where the filter really comes into its own.
A CPL filter cuts out polarised light entering a camera at different angles, allowing the photographer to enhance colour contrast and saturation in an image. You can darken a blue sky, to make it appear more dramatic, for example. This filter also gets rid of reflections and glare from non-metallic surfaces, such as water, rocks or foliage. By taking away reflections and glare, water appears transparent, allowing you to see the details below the surface. A CPL filter also excels when shooting through glass, as it eliminates annoying light streaks that undermine an image’s quality. Atmospheric haze can also be reduced from panoramic scenes. This adds clarity to distant objects such as mountains or buildings. The image-enhancing effects of a CPL filter can’t be recreated using post-production software.
A CPL filter works best when positioned at a 90-degree angle to the sun. Because of this, the filter doesn’t function as well on wide-angle lenses. These lenses allow for more than 90-degrees of light, thus resulting in uneven areas of colour on a scene.
When choosing a UV or CPL filter, both are circular and easy to attach to a lens. They are suitable for any type of photography, although landscape photographers prize them equally.
To conclude, if you’re looking for lens protection, a UV filter is the one to choose, whilst altering colour and reducing reflections and glare is better suited to the CPL filter. When deciding on a UV or CPL filter, remember that both are incredibly useful for different purposes, but always choose good quality filters.