How important are filters in the digital age?
Photographic filters modify the light coming into your camera, thereby creating effects during image capture. Filters are used to increase contrast, change color balance, and compress the dynamic range of a scene. In traditional film photography,the use of filters was commonplace, as film offered limited color choices and modest dynamic range. If you were shooting slide film (transparencies), what you captured on the film was pretty much what you’d get. Even the masters of black and white photography often used filters to improve contrast in a scene.
Photographic filters can be made of glass or resin, and are attached to the front of your camera lens either by a screw-in (ring) mount, or via a filter holder (square/rectangular filters). No matter what kind of filter you use, when you put a filter in front of your lens, you’re adding another glass/air interface for light to pass through. Low-quality filters can potentially degrade image quality by reducing sharpness, creating unwanted color casts, or introducing reflections or other artifacts into your photos. Your camera lens is designed to precise optical specifications; don’t ruin an image by using a cheap filter!
Filters have long been a major photographic accessory, and one question I’m frequently asked is, “what filter should I buy?” A lot has changed in the last 20 years, and digital cameras are much more forgiving than their film ancestors. When you couple the extreme dynamic range of modern digital cameras with the ability to post-process RAW images, a lot of “go-to filters” are no longer needed for most digital photography. Let’s take a quick look at the primary kinds of filters you can get, and whether they should take up space in your bag.