What are Filters Used for in Photography?

Filters are a great tool for photographers to enhance their images and create unique effects. They can be made of colored glass, plastic, gelatin, or sometimes a colored liquid in a glass cell. Filters are used to achieve image-enhancing effects that can change the tone and mood of photographs, inject slight but noticeable alterations into the image, minimize glare and reflections, improve colors, reduce light entering the lens, and generate fascinating effects that you can't edit in post-processing. Each lens filter has a specific purpose, as each is designed to offer a specific effect that can help improve the final look of an image.

Filters are optical accessories that attach to the front of the lens and can be made of glass or resin. They are a great piece of kit to carry with you in your camera bag, especially when you have been taking pictures for a while and are more up to date with the use of the camera. The following describes several key reasons and benefits of using filters, as well as how to use them and the different types of filters available. In monochrome photography, color filters affect the relative brightness of different colors; pink lipstick can be rendered like anything from almost light yellow to almost black with different filters.

Others change the color balance of images, so photographs under incandescent lighting show colors as perceived, rather than with a reddish tint. There are filters that distort the image in the desired way, blurring an otherwise sharp image, adding a starry effect, etc. Linear and circular polarizing filters reduce oblique reflections from non-metallic surfaces. The most common filter design is circular and screws directly into the thread on the front of the lens.

This type of filter requires that you have the correct size for the lens you plan to use or an adapter that fits multiple lenses. Even astronomical filters that do not use didymium are usually some type of narrow-passband color filter. Therefore, an ND filter helps capture the entire tonal range, from the brightest to the darkest parts of an image, thus achieving balanced exposure. A cross-screen filter, also known as a star filter, creates a star pattern, in which lines radiate outward from bright objects.

While in certain cases, such as in harsh environments, a protective filter may be necessary, this practice also has disadvantages. The filter allows you to balance exposure, preserving detail in both highlights and shadows, while capturing the scene in a single image. A polarizing filter can be used to darken skies that are too clear, as it increases the contrast between clouds and the sky. The gels are made not only for use as photographic filters but also in a wide range of colors for use in lighting applications, particularly for theatrical lighting.

Graduated ND filters alter the transition from dark to light, with 0.3 being a weaker gradation and 1.2 being a stronger gradation. Some GND filters have a hard edge for the transition from dark to light and should be used when the horizon is clear and flat, such as in a beach scene. However, Series 9 became a standard of the film industry and Series 9 filters are still produced and sold today, especially for professional cinematography. The Wratten numbers adopted in the early 20th century by Kodak are used by several manufacturers but the degree of correspondence between filters and numerical labels is only approximate. A strong UV filter such as Haze-2A or UV17 cuts off some of the visible light in the violet part of the spectrum and has a pale yellow color; these powerful filters are most effective at reducing haze, reducing purple fringes on digital cameras, and can subtly darken the pale blue sky improving the contrast between sky and marshmallow. For example, a yellow filter or more dramatically an orange or red filter will improve the contrast between clouds and sky by darkening blue sky and leaving clouds bright (after exposure compensation). You can even stack ND filters to block more light such as 3-point filter and 6-point filter to block 9-point light but if you use circular filters this can create vignette that will need to be cropped out of frame for final image. The most common standard filter sizes for circular filters include 30.5 mm 35.5 mm 37 mm 39 mm 40.5 mm 43 mm 46 mm 49 mm 52 mm 55 mm 58 mm 62 mm 67 mm 72 mm 77 mm 82 mm 86 mm 95 mm 105 mm 112 mm 122 mm 127 mm. Filters are an essential tool for photographers who want to take their images to another level by creating unique effects or improving existing ones.

With practice and experimentation you can expand your creative palette and take your photography skills to new heights.

Letícia Summerour
Letícia Summerour

Certified music lover. Wannabe pizza ninja. General food lover. Typical music lover. Avid pop culture nerd. Wannabe beer specialist.