UV filters in the digital age - Do I need one on my camera?
With the advent of DSLR and mirrorless cameras, UV filters have taken on a different role than originally designed for.
In the days when film was the dominant medium, camera sensors were much more sensitive to ultraviolet haze and radiation, and a multitude of other atmospheric particles that scatter or diffuse bright light.
Today’s digital sensors are far less sensitive to UV light as the sensors of the film era, and the UV now acts as more of a protective layer between the elements and your expensive and sensitive camera lens.
Here a few things to consider when looking for a UV filter as well as some tips on when to use one. We’ll also clear up a few common misconceptions about UV filters.
What price is right? - $9.99 or $199?
There’s a bunch of choices out there when it comes to a UV filter, from cheap to expensive, and made from optical glass, polyester, resin, gels or quartz. Determining which type you should pick up depends on the type of work you are doing, and also a matter of preference and of course price.
In a nutshell, you get what you pay for. A quality filter has a near perfect light transmission (meaning less light is refracted when passing through the filter) and yields a final image with the least image degradation. After all, adding any extra medium in front of your camera lens, no matter how optically pure, will cause some image degradation, even if negligible.
A quality UV filter will produce an image will no noticeable noise added, while with a cheap filter you begin to introduce more artifacts like lens flaring in brighter scenes, color casting, vignetting, or soft focus. So, if your question is really how much you should pay for a lens, consider the quality of your final composition.
If you’re using an expensive lens, it’s smart to use a UV filter in settings like the desert where sand, dust and other debris can cause damage to the front lens element. In a studio or indoor setting, you probably won’t need it.
A quality UV filter can also act as a weather seal, protecting the optical coatings on the front element from dust, extreme heat, or rain, as well as preventing the lens itself from fogging.
Let’s break down the UV filter by material and general use case:
Polyester: Polyester filters are durable and scratch resistant, and relatively inexpensive. Great for use on action cams as a protective lens.
Resin: Resin filters are similar to polyester filters concerning their protective properties. They are thicker than gels or glass filters, and so are not quite as efficient. Low quality resin filters will introduce chromatic aberrations.
Gel: Gelatin, or gel filters, are the thinnest filter option and are either reserved for studio use or in non-extreme environments. They usually are square or rectangular shaped and require a special mount that attaches to the front of a lens. The paper-thinness of gel filters means they will cause little to no noticeable image degradation. Gels also come in sheets that can be cut to fit directly over studio lights or windows.
Optical Glass: Optically refined glass is widely used by both outdoor and studio photographers alike because of its low refractive index and efficient light transmittance.
Quartz: Fused quartz filters produce a very low refractive index of 1.46 and offer outstanding temperature stability in extreme locations. Inherently scratch resistant and durable, quartz filters provide a more effective light transmittance than traditional glass filters.
Are Skylight filters UV filters?
In short, skylight filters have much the same effect as UV filters. While UV filters generally have a slight amber color cast, while skylight filters produce more of a pinkish tint.
There are two type of skylight filters; a lighter strength Skylight 1A, and a darker-toned Skylight 1B. Developed in the film era to compensate for the bluish tint caused by UV radiation, skylight filters are still popular in landscape photography today (though that blueish tint can also be fixed in post).
Final thoughts
-For outdoor use, including landscape, cityscape or action cam photography, a UV filter is useful as a protective shield against dust, rain and other atmospheric particles.
-A quality gel, glass or quartz UV filter will provide the best results while a cheap filter will degrade image quality.
-A UV filter will not protect your lens from internal damage caused by a hard drop, even if the front element stays intact, so do be careful with your lenses when out in the field!