A Guide to Filters for Lenses

If you ask most consumer-camera owners why they keep a filter on their lens, a majority will most likely reply, “For protection.” While filters do protect the surface of your lens against dust, moisture, and the occasional thumb print, the primary function of lens filters is really to improve the image quality of the pictures you take. There are many kinds of filters with obvious and lesser-known benefits, so if you’re looking for a lens filter, stick around! We are going to break down the basics  of lens filter and why they might be useful.

What are the basic filters?

The most basic filters are ultra-violet reducing filters, skylight filters, and protection filters. These filters are typically made of glass and feature basic anti-reflective coatings. You can safely use any of these filters to keep the front element of your lens clean and safe, but you’re going to want a UV or skylight filter if you are looking to also improve the image quality of your stills and videos.

Ultra-violet reducing filters, also known as UV filters or haze filters, are used to mitigate the effects of atmospheric haze, moisture, and other airborne pollutants that cause image degradation. Available in different strengths, UV filters are especially handy when you are photographing areas with intense ambient ultraviolet light. Locations near large bodies of open water, at higher altitudes, or in snow are all places where a strong UV filter (UV-410 and up, UV-Haze 2A, 2B, and 2E) will be useful. Because stronger filters use heavier UV coatings, some will have a warm, amber-like appearance that requires exposure compensation, typically anywhere from zero to a half stop.

Alternatively, skylight filters have a magenta tint and are available in two strengths 1A and 1B. These filters are preferable when photographing skin tones or using color slide film, because their magenta coloring can counterbalance the blue bias found in certain film stocks. Skylight filters can also cut through atmospheric haze like UV filters, but they do not impact your camera exposure.

What should I look for in a filter? Do I need to buy something expensive?

While most UV filters look the same, their pricing can be a big quality tell, often beginning with the kind of glass used in the manufacturing process. Make no mistake about it there’s glass and there’s glass, and the differences can really have an  impact on your image quality.

If you want premium glass, you’re going to want to look at factors like its thickness (the thinner, the better), the kinds of coatings used, how it was made and even where it was made. Usually, pricier filters use an optically purer and thinner glass that interferes less with the front element of your lens. Other factors to consider include the quality of retaining rings, prioritizing brass construction over aluminum that tends to dent and jam.

If your decision boils down to price, we recommend considering how you plan to use your filter. If you’re working with a basic kitted lens, or trying out filters for the first time, an inexpensive filter is totally worth taking out for a spin, but you will want to splurge on something of quality if you are working with a high-performance or telephoto lens. The money you might save on a budget filter is simply not worth compromising your valuable lens’s overall performance. 

What are Polarizing filters and how do I use them?

Polarizing filters are most handy when photographing outdoors, where they saturate colors and make clouds pop against the sky. They can also eliminate glares and reflections bouncing off water, glass, and other polished surfaces.

Like our other filters thus far, polarizing filters come in different flavors. They are available in two formats: linear and circular. Though they look and perform identically, linear filters are designed specifically for manual-focus lenses while circular filters can be used equally with AF or MF optics. Polarizing filters are also available in different filtration combinations like warming (81A, 81C, 81EF, 85, 85B), intensifying, and UV blends that can be handy for more specific working conditions.

Once you have purchased the correct type for your camera, simply mount your polarizing filter and rotate it until you have achieved the right level of polarization, keeping in mind that you will lose around three stops of light with it on. Overall, these little guys are great when working outdoors, optimizing your imagery in ways that cannot be mimicked with Photoshop and other post-capture voodoo.

What are Neutral Density filters and how do I use them?

Neutral density (ND) filters are gray-toned filters designed to absorb calibrated degrees of light as it passes through the lens. While they usually work in 1/3, 2/3, and full-stop increments, ND filters are also available as variable-density filters that you can infinitely adjust by rotating the filter on its mount as you would a polarizing filter.

There are many applications for ND filters, but chief among them is allowing you to shoot at wider f-stops under bright light. For this reason, ND filters are used extensively by filmmakers and videographers, offering better exposure control when working with limited shutter-speed options.

ND filters can also be used to blur pedestrian traffic and flowing water. Depending on the amount of ND filtration you place in front of your lens, you can drop your shutter speeds and control of how much or how little depth of field you desire for that silken, blurred effect.

What’s the difference between Neutral Density and Graduated Neutral Density Filters?

As the name suggests, graduated ND filters are typically clear on one end and gradually build in density toward the opposite end, while regular ND filters are even from end to end.

Graduated ND filters are often used to even out scenes containing extreme exposure variations on opposite sides of the frame. For example, a graduated ND filter might be useful if you are shooting a landscape where the top of a mountain is bathed in sunlight, while the valley below lies in shade. Indoors, this kind of filter is handy when your light source is overhead and gradually falls off as it approaches the floor. Graduated filters can also be used in evenly lit areas to darken the sky or foreground for stylistic reasons. You can even use a graduated color filter to add a little touch of color in a scene while darkening the foreground or background.

What about warming and cooling filters?

While warming (adding yellow to the scene) and cooling (adding blue to the scene) can be done post capture with editing software, some photographers prefer to filter their lens instead. This can be purely for aesthetic reasons, like warming up a portrait, or practical, like offsetting the bluer sunlight during the summer months. Warming filters encompass all 81- and 85-series filters, while cooling filters include all 80- and 82-series filters.

If you are applying a warming or cooling filter to a digital camera, be sure to turn off auto white balance and set your camera to meet to the ambient color temperature closely, i.e., daylight, overcast, tungsten, fluorescent, etc., of your scene for the best results.

I’ve heard landscape photographers talk about Enhancing and Intensifying filters. What makes them so special?

Enhancing and intensifying filters are modified to cut some of the orange portion of the color spectrum, which results in higher saturation levels in reds and a cleaner, less muddy interpretation of earth tones. They are especially popular for photographing fall foliage and landscapes.

I’ve seen photographers using red, green, yellow, and other color filters. Aside from making everything look red, green, yellow, etc, when should I consider using color filters?

While color filters do make everything look one color when placed in front of your lens, their most common use is for black-and-white photography.

When shooting black-and-white, a color filter can drastically change your image’s tonal qualities by preventing that specific color from reaching the film (or sensor) surface. By applying different color filters to your lens, you can enjoy creative effects specific to that color. For example, a yellow filter can be used to delineates clouds against blue skies, while orange and red filters will further intensify that effect. On the cooler side of the color spectrum, green filters can be used to improve skin tones in black-and-white portraits.

What are color-correction filters used for?

Color-correction filters, also called CC filters, include cyan, magenta, yellow, red, green, and blue filters. Available in 10% increments, CC filters are used to modify or correct the color balance of mismatched or irregular light sources. While they are less relevant in digital photography than film photography, many photographers still use CC filters to correct their images at the time of capture.

If you want to incorporate CC filters into your creative workflow, be sure to follow the same protocols as you would with other color filters. Disable your auto WB setting and use a setting closer to the ambient lighting conditions of your scene.

Are there filters other than the glass screw-on types?

While glass screw-on filters are the most common, there are also polyester, gelatin, and resin filters available. These variations are often square or rectangular and attach to your lens via either a filter holder or matte box. The filter itself is placed in a slot that will keep it flat and parallel with front lens surface to deliver optimal performance.

What are the benefits of polyester, gelatin, or resin filters?

These alternative filter types can be optically purer than glass depending on the type. This is especially true of resin and gelatin types, whose especially thin profiles can result in sharper imagery. These filters also tend to be lighter to transport when purchased as a kit or series, and will often end up being less expensive than a comparable set of glass filters.

Alternative filters are also handy if you have lenses with different filter threads. All you need is a single set of step-down rings to use with the filter holder. It is worth noting that the same set of step-down rings can also be used with screw-in glass filters, so there’s no need to purchase multiple sets of filters.

The main downside of non-glass filters is that they are easily damaged and nearly impossible to clean, especially when dealing with gel filters. If you intend to use non-glass filters, we recommend being extra careful when handling them, and purchasing a box of disposable plastic or cotton gloves.

What are slim filters?

Slim filters have narrow profiles and sometimes lack threads on the forward side of the filter ring. Available in almost every size, these filters are designed for lenses with an angle of view wider than about 74°, or the 28mm equivalent. Depending on the make and model, many kit zooms require thin or slim-mount filters. By utilizing a thinner retaining ring, the filter is less likely to vignette the corners of the frame.

What other types of filters are there?

There are many types of creative and technical filters available for pros and serious enthusiasts alike. There are filters that produce prism and star-like patterns, filters for close-ups, diffusion, infrared imaging, as well as contrast control. Their creative applications are up to you!

The Takeaway

• UV / Haze and Skylight filters protect the surface of your lens against scratches, dust, moisture, and fingerprints. They also minimize atmospheric haze, resulting in better overall image quality. Protective filters also keep dust, moisture, and fingerprints at bay, but are not effective in cutting through atmospheric haze.

• The difference between an inexpensive filter and a pricier one has to do with the quality of the glass (costlier filters tend to use purer and thinner glass), the quality of the anti-reflective and color coatings and retaining ring (better filters have brass rings instead of aluminum).

• Polarizing filters reduce or eliminate distracting reflections from the surface of glass, water, and other polished surfaces. They also darken skies, make clouds pop from their surroundings, and saturate color by reducing stray ambient glare.

• Polarizing filters are also available combined with warming filters, enhancing filters, and diffusion filters.

• Neutral density (ND) filters block varying degrees of light, making it possible to shoot at wider apertures under bright lighting conditions. They also blur moving objects and allow for better exposure control when shooting video or film.

• Graduated and color graduated ND filters use a gradient effect to equalize extreme lighting variables on opposing sides of the frame. They can also add an element of drama to spice up an image.

• Enhancing and Intensifying filters are useful for intensifying the color-saturation levels of reds and other earth tones, making them desirable for landscape and foliage photography.

• CC filters allow you to adjust the color levels of your cyan, magenta, yellow, red, green, and blue channels incrementally.

• Although most photographers rely on conventional glass screw-in filters, there are also square and rectangular filters made from out of polyester, gelatin, and resin. These filters can be optically purer than glass and require holders and extra care when handled.

• If you plan on using one filter on several lenses, you should purchase a slim or thin version to ensure it won’t vignette the corners of the frame when used on a wide-angle lens.

Overall, filters can be incredibly useful whether you are looking to enhance your imagery or gain some peace of mind in the field. If you are looking for solid filter recommendations, you can always leave a question in the comments, contact a B&H Sales Professional over the phone or live chat, or visit our SuperStore.

Do you have any tips for using filters? If you could only use one filter, which would you choose? Let us know in the Comments section, below.