The conventional wisdom in the days of film photography was to buy a UV filter (or a “skylight” filter) for each and every lens in your bag. The thinking was that UV filters provided some very minor positive visual effects, as well as acting as a cheap insurance policy/protection for the front lens element. The positive visual effect was always somewhat iffy to me, as I could never see a difference between UV filters, skylight filters, and no filter. But those relatively cheap little screw-in filters have saved three of my lenses from certain damage, so they are definitely worth it for that alone.
So Why Not Buy UV Filters?
Because they reduce the amount of light entering the camera’s sensor by a small amount. And, a UV filter does slightly change the color balance of captured images. You’re probably thinking, “I’ve never noticed any difference with a UV filter.” But you’ve probably never actually put this to the test. If you’re curious, a quick test with your camera on a tripod will provide you with images you can scrutinize. Take a photo with the filter on and then simply remove the filter and shoot the exact same shot. Pull both images into your editor of choice and look at the white balance information. You may see a shift of 25 degrees Kelvin in the data. But it’s also possible you may not notice visually on your screen. Either way, why have anything unnecessary between your lens and all that glorious light?
What’s the Alternative?
The simplest alternative is to buy a clear glass screw-in filter. Most popular filter makers offer them, although they are usually hard to find in search results because UV filters are the most common. Tiffen makes a nice budget-priced clear glass filter in several sizes. You can pay more for a premium brand, but for clear glass, why bother? Save that extra cash to put towards a lens upgrade!