Search any photography forum and you’ll soon discover that one of the most frequently asked questions to feature is whether you can leave a UV lens filter on at all times.
There’s no right or wrong answer to this topical question. Some people leave UV lens filters on all the time and wouldn’t have it any other way, whilst others think that putting an extra layer of glass in front of a camera lens can degrade image quality or cause lens flare. There are also other photographers who prefer to use a lens hood for protection.
What is certain, is that UV filters offer lots of benefits to the photographer, and they’re easy to take on and off your lens, without causing any wear and tear to the threads. If you shoot outdoors, having a UV lens filter permanently on your camera offers great protection against the elements, such as preventing dirt, dust, sand, moisture, smears or scratches from getting near the actual lens. After all, it’s much cheaper to replace a UV filter than a camera lens!
For landscape or outdoor photography, keeping a UV lens filter on for protection certainly makes sense, and if you choose a really good quality filter, studies have proven that it shouldn’t have any negative impact on image quality or cause lens flare or ghosting, provided you don’t use it at night or in artificial light. Although modern digital cameras can effectively block out UV light themselves, a UV filter can help to remove the blue cast you sometimes get when shooting in extremely bright conditions.
However, if you shoot indoors all the time and don’t want anything to come between your camera lens and your subject, perhaps there’s less of a case for keeping a UV lens filter on all the time.