FILTER TYPES

Understand the pros and cons of different filter systems

Filters come in two main formats: round filters that screw onto the filter thread of your lens, and square/rectangular slot-in filters that attach via a holder. Each type has its pros and cons.

One of the main reasons to use threaded filters is to protect the glass front element of your lens; far better to pick up a scratch on a replaceable filter than on the lens itself. The downside to screw-on filters is that they aren’t a one-size-fits-all solution. If you have lenses of different diameters you’ll need to purchase separate filters for each lens, or use stepping rings to adjust the fit. This isn’t such a problem with UV filters as these are inexpensive, but start getting into the more technical filters and costs can start to soar.

It’s also important to note that when adding any sort of screw-on filter to a wide-angle lens, be sure to use a low-profile filter to avoid any vignetting from the exterior metal element.

UV filters

The most common type of screw-on filter is the UV filter, which filters out ultraviolet light. In the days of film, some photo films were sensitive to UV light, which could show up as a blue haze in your photos when shooting on sunny days or at high altitude.