Camera Lens Filters Explained

Lens filters can be transparent, translucent or gelatin glass elements or lenses that attach to the front. Lens filters protect the camera lens and alter light transmission characteristics. They can also add color effects to images. There are two types: slot-in and screw-in filters.

Screw-in filters

Srew-in Filter Types

Screw-in filters attach directly to your lens by inserting into the threads near the barrel. Each screw-in filter has a specific width. Therefore, the more lenses you have (of different widths), the more filters that you will need. Screw-in filters make it easy to swap between polarizers or UV filters.

Slot-in Filters

Slot-in Filter Types

A filter holder for slot-in filters is attached to the lens’ adapter rings. Filters are then dropped into the holder. Most holder have interchangeable rings, so it can be used with a variety of lenses. The holder usually has three to four grooves so that you can place more than one filter inside. Slot-in filters have the advantage that you can quickly add and subtract filters. Larger filters can also work with smaller lenses.

Filter Factor

Filters alter the dynamic of light entering the lens. They can also cause you to adjust your exposure to compensate. This is known as the Filter Factor. Each filter has a unique filter factor. Learn how to use them.

UV Filter

UV Filter

Ultra Violet filters are transparent filters which block ultraviolet light. They reduce the visible haziness in daylight photography. Because UV filters do not block most visible light, they can be used as a form of lens protection. They will not affect your exposure. Some UV filters are stronger and more effective in cutting atmospheric haze, as well as reducing purple fringing. Purple fringing can be seen around the edges of subjects when they are slightly out of focus.

Polarizing Filter

Polarizing Filter

Polarizing filters can be used to darken skies that are too bright. They increase the contrast between the sky and clouds. The Polarizer, like the UV filter reduces atmospheric cloudiness and reflects sunlight. A Polarizer’s primary function is to reduce reflections from glass and water. The Polarizer removes reflections from water and glass when properly angled or spun. This is a useful trick! There are two types: circular and linear polarizers. The effect of both types of polarizers is similar, but the circular polarizer removes unwanted reflections with the aid of a quarter wave plate. This image has no reflections and is free from reflected light.

Color Balancing Filter

Color Balancing Filter

You know that visible light can be divided into multiple colors. Photographers have to choose whether to use the white balance of the camera to capture the whitish light of daylight or the reddish-orange incandescent tungsten light. There are a few variations, e.g. You can choose to use fluorescent or sodium-vapor. This is what the White Balance is designed to control. To adjust your light sources, you can use a Color Balancing filter. To compensate for differences in light colors (e.g., daylight is cooler and appears bluer), you can use a Color Balancing Filter. The color of daylight appears cooler and more blue than that of tungsten, which appears warmer and more reddish-orange. Two standard filters that can be used to compensate for color balancing are the 85B (warm up/orange filter), and the 80A (“cool down/blue filter”) The 85B allows you to photograph in daylight when the white balance/color temp is set for tungsten. Your image will be blue without the 85B filter. The 80A allows you to shoot in tungsten light if the color temperature/whitebalance is set for daylight. Your image will look abnormally warm/reddish-orange without the 80A. This type of color correction can be easily achieved using image processing software. They are used by some photographers for artistic effects.

Filter for Neutral Density

Neutral Density Filter

A neutral density (ND), filter can be attached to your lens to reduce the light entering it uniformly. The ND filter can be useful when there is too much contrast between the highlights/shadows to achieve a good exposure. The ND filter can also be used to enhance motion blurring and image detail. It allows for a larger aperture and/or a slower shutter speed. The graduated ND is another variation of the ND filter. This filter has a gradient that reduces light at a neutral level, from 100% to 0%, along the filter’s length. For landscapes and seascapes, the Graduated ND is recommended because it can reduce the brightness of your sky to improve contrast but not affect the exposure of the land or water.

Soft Focus Filter

Soft Focus Filter

Soft focus filters do exactly what they say. They reduce the sharpness of images but not to a level that is noticeable. These filters are great for taking close-up shots of people’s faces. A little diffusion can make even the most difficult skin conditions look silky smooth. You can also use soft focus filters to photograph landscapes and monuments.

B&W Photography Filters

Red Filter used for B&W Photography

B&W photography has specific filters that can lighten or darken colors in a similar way. This enhances monochromatic looks. B&W photography can be done with Red, Orange Yellow, Green, and Blue filters.

Landscape photographers love red filters. They are used to add drama. A red filter can be used to increase contrast between green leaves and red flowers in nature photography. A red filter can deepen blue skies and make white clouds stand out. It can also reduce the effects of fog and haze. A red filter can be used to make the sky black, depending on how strong it is.

Orange filters enhance contrast between textures like bricks or tile, so they are a great choice for urban and abstract photography. Although it reduces fog and haze, its effects on the sky are more subtle than those of the red filter.

Yellow filters are subtler than orange filters. This makes them a great choice for beginners who just want to learn how to use black and white filters. It darkens the clouds slightly and separates the lighter shades from the darker.

Green filters lighten dark green foliage and boost light green foliage. Although they are less common than the other filters, green filters can be extremely helpful for nature photographers. The lightening effect of green filters can be beneficial for landscape photographers.

Because they can lighten skies and darken highlights, or colors that are perceived as light, blue filters aren’t as common in black-and-white photography. Blue filters can be used to draw attention to fog and haze, which can improve the mood of the photograph if necessary. This filter can be used to create a B&W image, which is a better option than shooting in color.

A filter absorbs light so it requires an increase in exposure. A “filter factor” is a measure of exposure compensation that filter-makers suggest. A filter factor of 2X is a multiplier of the exposure by 2. If your filter factor is 4X, you should increase your exposure by 4. Add 1 f/stop to your exposure if the filter factor is 4X or 2X. Alternativly, divide your ISO by filter factor. Your new ISO will be 100 if the filter factor for 200 is 2X.

Conclusion

You can use photographic filters to enhance your photos. They can alter the mood and tone of your images. Filters can make subtle, but noticeable changes to your image. While you can achieve similar effects using Photoshop (or other image manipulation software), you can instantly see the changes in your image through the viewfinder when you apply a filter. B&W is more susceptible to the effects of filters because the monochromatic scale reacts differently and has a greater dramatic effect. Practice and experimentation are key to expanding your creative palette, just like with any new accessory.