Some of the most-utilized items that photographers have are lens filters. These give photographers ways to control color, reflections, highlights and more. But what filters should you get, and when should you use them?

UV Filters

As a beginning photographer, I used UV filters on all my camera lenses. They gave me a way to protect my valuable lens glass from scratches, dust, dirt and pesky fingerprint smudges. It also meant that I wouldn’t have to worry quite as much should I drop my lens while shooting, as it would protect the glass.

But I soon learned that UV filters can negatively impact photographs (primarily a reduction of sharpness) because it’s adding another layer of glass between the lens and the subject.

UV filters were popular during the film days, as it gave photographers a way to block UV rays from impacting the film. Because digital cameras come with a UV/IR filter directly in front of the sensor, there’s no need to worry about this anymore.

For this 15-second exposure, I was able to capture movement in both the sky and the river on a sunny day. This wouldn’t have been possible without the 10-stop ND filter I used.

ND Filters

If you’re a landscape shooter, you probably already know about Neutral Density, or ND, filters. Simply put, these reduce the amount of light to your camera. Doing so allows you to slow down your shutter speed, making for the perfect setup for daytime long exposures.

There are several levels of ND filters, most commonly in 3-stop, 6-stop and 10-stop variants. Each stop reduces the amount of light by half, meaning the higher the stop, the less light you’ll see brought into your image. You can stack these filters too, letting even less light in.

Beyond the solid ND filter, there are also graduated ND filters, allowing you to darken only part of your image. These can be useful for when you have a bright sky but an otherwise dark landscape, as it’ll help to balance the level of light present.

Circular Polarizing Filters

Polarizers are popular with photographers who want to control reflections, glares and contrast in their images. Think of a polarizer filter like putting on a pair of sunglasses on your lens — it helps to balance out the light, making for a more accurate exposure.

Using a polarizer can help to get rid of reflections so you can see underwater, and it can also help when shooting through glass windows. Landscape photographers will also love circular polarizers for reducing haze in an image, or to darken a sky.

In the two photographs below, notice how the watch on the left has a visible softbox and other reflections. With the photo on the right, using the polarizer makes these reflections not as prevalent, and also helps to make the watch face appear larger.

One thing to keep in mind about polarizers is that they typically give a loss of around two stops of light, meaning your shutter speed will have to slow down to keep the same exposure.

When shopping, be sure to purchase a circular polarizer, and not a linear polarizer. Linear versions are meant for older film cameras and can result in some light metering issues. Circular polarizers are meant for today’s modern camera bodies and lenses.

Other Types of Filters

While UV, ND and Circular Polarizing Filters are the most popular for photographers, there are a few others you’ll want to keep in mind as well:

Color Filters

While polarizers help to balance the level of light that comes into your camera, color filters help to balance the color that comes into your camera. Often known as CC filters, these let you adjust the cyan, magenta, yellow, red, green and blue levels in your images. In today’s digital camera world, these are less popular as you can change white balance to compensate instead of using filters, which also reduce the amount of light.

Special Effect Filters

Because of the advances of post-processing software, it’s rare to see these today. In their heyday, there were special effect filters that allowed you to apply effects such as a soft glow, motion blur, additional bokeh and more.

Macro Filters

In need of a macro lens but don’t have the cash to break the bank on one? Look into a macro (or close-up) filter — a cheap, easy way to convert a lens to a macro lens. While these will give you a macro photography look, they do have a tendency to impact image quality.

How Do I Know Which Brand and Size to Buy?

There are a ton of different filters out there, so it can be confusing if you’ve never purchased one before. The first thing you’ll need to know is your filter thread size. This is usually marked at the tip of your camera lens. It’s usually something like ø58, which means it’s a 58mm diameter. A good tip is to buy the filter to match your largest lens, and then use step-up rings to make it fit your smaller lenses.

From there, it’s important to know the differences between filter materials. You’ll pay a premium for better filters just like you would lenses — and better filters are often thinner, meaning they’re less likely to cause vignetting in your images. Filter rings made of brass instead of aluminum are also usually recommended because they don’t seize on the front of the lens as steel and aluminum filters can.

Conclusion

A photographer’s toolbox is endless. Between camera bodies, lenses, tripods, flashes and more, there’s a lot to take into account. Using filters is a great way to control certain variations of your images without having to rely on advanced post-processing tools.