Polariser Filter

A big issue that filmmakers have a love-hate relationship with is reflections. It’s like this crazy hot and cold relationship where sometimes we want reflections around and other times we want them to get lost. So with this complex love-hate relationship with reflections in mind, one of the very first accessories I would get with any camera is a circular, polarizer filter. After the ubiquitous ND filter, which is already built into many cameras. I think the circular polarizer filter is a close second for all around practical usefulness and production value bang for the buck.

Polarizers have several uses, but the most common is to cut down reflections. No matter what situation you’re in, there are almost always reflections of one type or another, on car windshields, glasses, windows, water, even on faces. A polarizer filter is the one thing that can deal with all those issues quickly and effectively and help you control the level of reflection in almost any scene. So let’s take a closeup look at the handy circular polarizer filter in one of the most common scenarios and that’s shooting through glass.

Let’s start with the standard window scene. Here’s our scene without a polarizer. As you can see, we don’t see much of our actor’s performance here. Instead we mostly see the reflection in the glass outside of the office. So things like the expression on their face, wardrobe, and important props in the scene are all much harder for the audience to see. Now if you don’t have a polarizer filter, you can try things like different camera angles, or maybe a large flag or other types of rigging to block light from hitting the window, but either of these solutions would be more time consuming, and it’s still hit or miss as to whether it would even work to cut out a good deal of the reflection.

So we’re going to do what we must do, just like the pros, and bust out a circular polarizer. Once your polarizer is on the lens, look through the viewfinder as you slowly spin it and you will instantly see the value of the polarizer as it significantly reduces the level of reflection, so that we now see our actor clearly on the other side of that glass window. Now, another common scenario that calls for a polarizing filter is car shots. Driving shots are a nice way to keep things dynamic onscreen, with motion and changing light and backgrounds.

However, not unlike the office scene I just showed you, many people go to shoot their car scenes only to discover that all they’re really shooting is the reflection of the sky and trees above, and very little of the actors behind the glass. Again, a circular polarizer is just the solution. The beauty of this type of polarizer is that it’s not an either/ or choice of reflection or no reflection. Instead it allows you to control the degree of reflection. Those leaves and sky reflecting on the windows are often a beautiful and complementary visual element to the story.

They also help to aid the sense of motion. So many times you’ll find that sweet spot that allows some reflection – just not enough to obscure your actor’s performances. Remember, there’s not a right or wrong way, per se. Just a right or wrong level of reflection for the particular visual story you’re trying to tell in any given scene. Sometimes that will mean a full focus on the reflections in the scene. And other times it may mean eliminating those reflections. It’s your thing so do what you want to do. The important thing to take away is that only a circular polarizer allows you the choice to easily control reflections on glass.

And to be clear, removing reflections is not something that you can do in post. They don’t have an app for that, at least not yet. So a polarizer is a vital tool to have. When you need to manage reflections in glass surfaces. But controlling reflections is just the most popular use of polarizers. In future, I will explain how a polarizer can also be a handy tool to help you control the look of water and the sky. As well as the saturation of colours and foliage. So stay tuned.