Lens Filters – Should You Use Them?

This subject came up recently in my online photography group. I thought I’d turn it into an article for the blog.

Should you use lens filters? I’ve seen this debate percolate on the Internet for years. I’ve seen it occur in camera clubs over and over again. I’ve talked to many photographers in workshops and in the field. I have my opinion, and I’m sticking to it.

The discussion continues…

I’ve included a couple of comparison photos for the purposes of my opinion.

UV filters.

Photo taken with a Canon EOS 5DSr using a UV filter. 100% crop of a 50.3 megapixel original RAW file.

 

Photo taken with a Canon EOS 5DSr with no filter. 100% crop of a 50.3 megapixel original RAW file.

Both photos were taken in the San Juan Mountains of Colorado of landscape scenes using the Canon 5DSr and a 24-105mm L lens. The camera was mounted on a tripod both times.

These are just tiny little slivers of the actual image, cropped to about the same distance from the camera at roughly the same camera settings.

If you examine the two images, you can see that the first image taken with a UV filter mounted to the lens is much less sharp than the second image, taken with no filter on the lens. I found out the evening of the first photo that every shot I took using a UV filter was coming in more blurred than shots that I had taken without the filter. It was a good quality Hoya UV filter, made of glass, not plastic.

So here’s the rub.

The debate concerning UV filters usually comes down to those who use them saying it’s for protecting their lens. It’s an old debate and more or less originating from camera store sales people trying to convince you to spend another 60 bucks on something you don’t need. It’s become a common misconception and I can not tell you how many times I’ve seen people with a UV filter on their lens spouting that mantra.

The truth. The UV filter is the most worthless camera accessory you can buy. If you are using one to protect your lens, you are probably degrading the quality of your images. Most UV filters, particularly the cheaper filters are made of plastic. some more expensive filters are made of glass. Either way, what you are doing is putting a cheap piece of glass between your lens and your photographic subject. The net effect is something akin to taking photos through the window of your car. As for protecting your lens, well, that sounds all warm and fuzzy, but a better lens protection is the lens cap and lens hood that came with your lens. If you want to protect your lens, put the lens cap on it until you need to take photos. If you’re walking around with the camera, the lens hood will give you protection from bumping your lens up against a rock or fence or something. If you drop your lens, you’ll probably do more damage to it than any filter could prevent. Don’t waste your money, don’t waste your time, don’t ruin your photos.

What about other filters?

Neutral Density Filters.

The only useful filter in my opinion is a neutral density filter. Filters were a staple of film photography, designed to manipulate the tonal and contrast qualities of film. With digital editing tools, you have much more control. plus you aren’t slapping a hunk of plastic between your lens and subject. Still, they are useful for reducing the amount of light, thus increasing exposure time on moving water scenes such as waterfalls or streams. Other than that, not much benefit will be obtained by using them and you still have some image degradation to contend with.

Polarizing Filters.

I am ambivalent about polarizing filters. They don’t work well on super wide angle lenses, as they can have an uneven effect. But, in some situations they can help. Example, bright reflective objects (specular highlights) can be muted. I always found them usable in tropical waters. They can bring out some of the color in some situations. But, I’ve ruined more than a photo or two with them as well. Color enhancement can be done in post processing just as well most of the time. Two main drawbacks though. One is forgetting you have it on the lens and then finding out later that you’ve been shooting with a misadjusted filter. Second, with a circular polarizer you are effectively putting two panes of plastic in front of your lens, which doesn’t improve image sharpness and can create weird reflections in the image.

Snapshot of a scene where I had a circular polarizer on the lens that wasn’t adjusted for the angle of the photo.

Notice the dark part of the sky on the left and the bright part on the right. This is what happens when you have a misadjusted circular polarizer on your lens. Operator error, yes. But if you put a circular polarizer on your lens, you better remember it’s there before you start shooting. Another area of concern is creating a panoramic by stitching a series of photos taken using a circular polarizer. My advice, don’t do it. You’ll have nothing but uneven skies to deal with when you stitch those shots together.

Color Tinted Filters.

Why? You can do more with post processing to change the tonality of your image than you can with a tinted filter. You still have the image degradation issue by putting a hunk of plastic between your lens and subject.

Other filters.

Artsy-fartsy stuff such as star filters and such, only good for getting a 70’s canned look. You can still do more with post processing and you can still fix it too.

To conclude my thoughts. I’ve never taken a photo and afterwards said to myself “If I’d only used a xxx filter on this shot, it would have been better.” I have taken many photos using a filter of one type or another and said afterwards “If I hadn’t used a filter, this shot would have been better.”

Bottom line. Dump the filters. Lens manufacturers put a great deal of effort into making their lenses filter out unwanted artifacts from the light that transmits through the lens. Why on earth would you want to slap a cheap piece of plastic on your lens to make the image look better? All you are doing is increasing the likelihood that you will ruin your photo.

Just my opinion, but I’m sticking to it.