Circular polarizing filters, a.k.a. “polarizers”, are some of the few filters I always have in my pack. Polarizers are important tools in my landscape photography. They can dramatically enhance the look of skies, water and other features of the landscape. Polarizers can remove unappealing glare. They can increase the vibrant color and help the detail of a scene burst through. As with many pieces of photo gear, it’s easy to label them as something you use for only a certain type of photography. I once thought of my polarizers as something used for only landscapes, leaving them in the truck anytime I was out after wildlife or macro photos. But, they can be used for all types of subjects. To help reveal textures and richer colors, or create interesting effects in your image. In this article, I’ll share the many ways I use polarizer filters, so you can put them to use in your photography.
Why use a Circular Polarizer?
The main reason to use a circular polarizer is to remove shine from objects caused by reflected light. This shine, really it’s glare, obscures details and colors. That makes scenes seem hazy or washed out. While polarizers will have the most impact on smooth surfaces, you can see a difference in the appearance of all types of subjects. One example is with plants. When light strikes a leaf some of it is absorbed, while the rest of the light bounces off in different directions. Some of it appears as shine. Shine hides the true colors of leaves. It causes them to appear faded with their details to be obscured. Using a polarizer can remove this, depending on the angle of the light, and allow the true colors and textures of the plant to (heh) shine through.
I often use polarizers in macro work, especially when photographing things like insects, water droplets, flower petals, or other potentially shiny objects. Many bugs have very shiny little exoskeletons. In fact, mentioning that is one of the nicest compliments you can give them. Shine isn’t always desirable in our images, removing it can make an extreme difference in the appearance of the details and colors in your new little friend.
Monarch Butterfly in chrysalis, notice how the shine on the outside of the chrysalis is removed when the polarizer is used.
Although I rarely use polarizers on wildlife, in some very specific cases using one can produce a very cool effect. Many species are shiny, particularly, reptiles. Using a polarizer can remove the glare to show the intricate patterns and detail of their scaly skin.
They can also be handy when dealing with aquatic creatures, like alligators, otters, seals, and other swimming critters. Not only does it remove the shine on their wet skin/scales/fur/etc., it can also remove the shine from the water, revealing their shape below the surface. For creatures like manatees or dolphins where you may only see a snout poke above the water, this can add scale and shape to your subject.
Using a polarizer with wildlife comes with a few catches. The large lenses often used in wildlife photography require either a very large front filter, or they take only drop-in filters. Both of these options are fairly specialized and expensive. Next, you should always be shooting with your lens hood on outdoors, but the lens hood makes it cumbersome to adjust the polarizer. Finally, you usually want to have high shutter speeds to freeze animals in action. The polarizer will cause you to lose between one and three stops of light, effectively making your shutter speed lower at the same aperture as without the filter. Adjust to a higher ISO to help make up for this loss.
Products and Still Life
Especially in items that include glass or other potentially glare-happy materials in their construction, a polarizer can help tame that shine. In particular look at the glass over the face of the watch. Without a polarizer, the reflections in the glass partly obscure the details of the face of the watch. Adding the polarizer removes that glare, but also notice how much richer the gold color of the watch is.
If you were out shooting on a hot day, or in a stuffy studio, and your subject has sweated their way through the shoot, using a polarizer can save you much work afterward in the digital darkroom. The filter will help remove the shine on sweaty skin, as well as in the surrounding environment. It can also remove some glare on eyeglasses, jewelry, and all sorts of other shiny, potentially distracting, things your model may be wearing.
A lighthouse photographed from below. The lines and geometry of this really caught my eye, so I played around with compositions here for a long time! The polarizer removed bright shine on the door and structure, showing more detail and reducing the contrast. Building photos benefit much the same way as landscape images do by using a polarizer. Reducing shine on the surfaces of the structure can reveal details, textures, and embellishments which the glare may have hidden. Another use is to remove reflections from windows so that you can see through the glass to the scene on the other side. This works well for shots from inside or out, revealing interiors or pretty views outside the building.
Because you are filtering light, not as much light is reaching your sensor as it would without the filter. This has a very tangible effect on your settings, as the filter is taking away between one and three stops of light. When thinking through my settings, I generally start out on Aperture Priority (or Manual in constant light). Selecting the f-stop to achieve the depth of field needed to get the subject in focus, while rendering the background and foreground the way I want them to appear. If you have chosen your aperture, and then remove some of the available light, you will have to make a compromise in your other two settings. Either by increasing your ISO, at the expense of increasing visible noise, or by slowing your shutter speed, at the cost of anything moving in the scene becoming blurry.
It is not that this is a bad thing, it’s just a characteristic of using a polarizer. In landscape photography, polarizers are often used for just this reason, to lengthen the time your shutter is open. This allows the action of things moving in the scene, like the water in waterfalls or waves in the ocean, to blur. Other features of the landscape that aren’t moving will remain sharp (so long as you’re on a tripod), while the water will take on the ever popular dreamy/silky effect.
Beyond landscapes, combining a polarizer with a low ISO and a small aperture (think double digits (f13, 16, etc.) can increase the shutter speed to a point where the action begins to blur. You can use this for an artistic effect to imply motion, like with running or flying animals, racing cars, or flags waving on a windy day. Want something to look like it’s going fast? Put on a polarizer and slow down your shutter speed.
Sometimes Reflections Define the Subject
Think of a water glass for a moment. The glass and water themselves are transparent. Reflections define the shape and edges, giving the glass a more three-dimensional appearance. Sometimes using a polarizer can make the glass look flat and dimensionless, but sometimes it can really help.
When Removing Reflections is too Revealing
Think in terms of landscapes, you can see this effect most commonly in waterscapes, where you pop on your polarizer only to find the pretty blue water now looks like a mud puddle. As the reflection of the blue sky is removed, you see the less than pleasant muddy bottom beneath the water. Sometimes you want the shine and reflections to hide what is underneath the surface.
This same thing can happen in many other subjects, for example in the spider web below. Rainbows are reflected light, a polarizer will remove all or part it, in this case, the plain web would appear instead of all that crazy color caused by reflection/diffraction through it. (You can read more about them here: How to Capture Fantastic Photos of Rainbows)
At some point, the mistake all of us make as photographers is we go through a phase where we apply the new trick we learned to everything we shoot. Although there are many cool things you can do with a polarizer, it’s not something you should shoot with all the time. Don’t be afraid to get creative with it, but there are some subjects and situations where it will definitely not work well.