Back in my film days we all bought a UV filter for our lenses, primarily for lens protection but also because filtering out UV wavelengths was good for film. On today's DSLRs there is a UV filter embedded in the sensor, so protecting from UV waves with additional glass is pointless, and only provides a way to downgrade the lenses' performance by putting crummy glass in front of it. So what about protection? Read this:

https://www.lensrentals.com/bl...rotection-revisited/

For what it's worth, I put Nikon Neutral Clear (NC) filters on my lenses for protection, but do take the filters off when conditions are good and no protection is really necessary. I only use two other filters (and only rarely) which are a Circular Polarizer (Nikons are good) and a Neutral Density filter (the Hoya Pro ND1000 is a good one). I would even recommend using these filters whatever brand of lens you use. For the most part I only use these last two when I'm doing some sort of dedicated photo outing with a tripod. The absolute best are probably these:

http://breakthrough.photograph.../x4-neutral-density/


But if you use an old cheapo UV filter for protection on your lenses, take them off when you're shooting in good conditions. Especially if you invested in really good lenses. All you will accomplish is a degradation of what your lens can do.

Very good point. I could never see the sense in buying a quality lens, with elements carefully ground, matched, and coated, and then sticking cheap piece of glass in front. Might as well take photos through a window.

I realize there are some optically excellent filters but they aren't cheap. I've used good quality Nikon and Canon lenses for over 40 years and never damaged one.

I do believe in using lens hoods and lens caps whenever possible, also in keeping lenses clean. Except when actually taking a photo the lens cap is most likely on. Removing/replacing the cap can become a conditioned reflex if you do it often enough.