When and how to use a circular polarizing (CPL) filter – Full guide

When to use a circular polarizing filter

CPL filters work best when there is a lot of light. They are incredibly versatile and can help you take better photos in various situations.

Reducing reflections

The most common case of using a circular polarizer is for removing reflections. When photographing through windows, glass or other reflective surfaces, a CPL filter can help to eliminate them and capture what’s behind the glass with clarity.

Shooting water scenes

When you want to shoot a landscape with a sea, river or lake where you can see through the water, a circular polarizing filter is something that you need. By reducing reflections on the water’s surface, the filter will reveal the submerged textures and details. This can make a photo more interesting and deep. A CPL filter will also remove reflections from wet stones and rocks allowing to capture their true colour without highlighted spots.

Capturing photos of foliage

Circular polarizing filters reduce glare and reflections also on the leaves. This enriches the colours of foliage, flowers and other vegetation. As a result, greens, yellows and reds become more vibrant and intense.

Photographing the sky

When shooting landscapes with the sky, a circular polarizer can be used to deepen the blue hues of the sky, making the sky more vibrant and clouds stand out.

Enhancing colours

A circular polarizing filter intensifies colours making them a bit darker and richer. The photos taken with it have a better contrast.

When NOT to use a polarizing filter

Even though a CPL filter is a really handy and useful tool in photography, in some situations it’s better to leave it off.

Keeping the reflections

Sometimes, you may want to include some reflections for artistic effect. For example, if you're aiming to capture reflections of coloured light, such as sunlight dancing on water, it's better to skip the polarizer. These reflections can add interest and depth to your images, and the filter will just ruin the artistic part.

Shooting in low light/at night

When shooting in low light or at night, the reflections usually are not a problem. On the contrary, you may need to add more light to capture the details of the scene. With the circular polarizing filter reducing the light by around 2 stops, you risk taking an underexposed image. It’s not a good idea to use a CPL filter in the blue hour either.

When shooting with the sun behind you

The polarization is most effective when the light source is at a 90-degree angle to your shooting direction, so if the sun is right behind you there won’t be much effect.

Shooting panoramas

When capturing panoramic scenes, using a circular polarizer can lead to uneven polarization and darkened parts of the image. If you want to maintain consistent brightness and colour saturation across the panorama, it's best not to use the filter.

Using wide-angle lenses

Similarly to the issue with shooting panoramas, wide-angle lenses do not allow for an even polarization. When using a CPL filter with this type of lens, you are most likely to get dark patches on the sky and vignetting.

Using polarizing filters in different types of photography

Now that you know what effects you can achieve with a circular polarizing filter, let’s see how they can help in different types of photography:

• Landscape photography: Rich blue skies, transparent water bodies with aquatic life, vibrant colours – that’s what CPL is used for.
• Architectural photography: Eliminate annoying reflections on glass buildings to capture clean and crisp shots of urban scenes.
• Product photography: Remove unwanted reflections from the products to show their true look. Particularly useful when shooting jewellery and watches.
• Car photography: By reducing glare and reflections from shiny surfaces with a CPL filter, you can capture the true colour and texture of the car.
• Outdoor portraits: Reduce glare from the skin and improve the overall contrast of the image.

Tips for effective use of circular polarizing filter

1. Avoid over-polarization: Always check how the image looks like on the screen and adjust the filter before shooting. Too much polarization can make your skies look unnaturally dark.
2. Adjust the filter: Lighting conditions can change rapidly, especially when shooting outdoors. Do not forget to adjust the CPL filter accordingly as you move from one scene to another or as the sun changes position throughout the day.
3. Check the settings: A circular polarizing filter reduces the light entering the lens by around 2 stops. You may need to compensate for the correct exposure.
4. Practice, practice and more practice: Experiment with different settings, scenes, and filter combinations to find what works best for your unique style.

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More about CPL filters:

What is a CPL filter and how it works


Shooting portraits with polarizers

Polarizing filter in landscape photography

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