Granted, I made that last part up, but the fact that I invented it doesn’t make it less of a truth. Using a dirty camera lens is like looking at the world through a dirty window, and even a few tiny specks of dirt or rain will affect the photo you’re taking. Just look at the image below—it’s a great shot except for the blurry bit right in the middle caused by a water droplet on my lens. There are also a few other less obvious blurs and smudges throughout the image. While this is mainly an issue with DSLRs and mirrorless cameras, a drop of water or a fingerprint smudge on your smartphone lens will also affect the photos you take. Just remember that time you were eating greasy fries and when you pulled out your smartphone to take a picture you realized all the lights on the street looked elongated on your screen. So, even if you only shoot with your phone, you should still do your best to keep the lens clean.
Clean your lenses regularly
The simplest way to make sure you’re shooting with clean lenses is to regularly clean them yourself. If you’re out shooting and notice a dust spot or two in your images, you can do it then, but it’s better to preemptively clean your lenses in the quiet and safety of your own home. You’ll have more time, better tools, and run a lower risk of making it dirtier by just spreading smudges around. Cleaning a camera lens isn’t hard, but you will need to be a little bit careful—if you do some real damage, it will be expensive to repair or replace. You don’t need to be scared, though—the outer element of a lens is designed to stand up to a bit of abuse, so unless you go at it with a wire brush or break out the industrial bleach, you’re unlikely to scratch it or strip away its protective coatings. It’s a good idea to make a habit of cleaning your lenses every time you shoot—it’ll only take a minute or two. You can either do it before you head out or—as I prefer—while importing your images to your computer after shooting. Your lenses are unlikely to get dirty when they’re not in use and have a cap on, so if you follow this advice, they’ll always be ready to go, even if you head out in a hurry. There are three things you’ll have to clean off your lenses: dust, dirt, and smudges from fingerprints or evaporated water. There are different tools and techniques for getting rid of each one.
Get rid of dust and dirt with a brush or a blower
To get rid of dust and dirt, the best tool is either a lens brush or a manual air blower. A lens brush has soft bristles specifically designed not to damage camera lenses, so don’t use a toothbrush or a makeup brush instead. They’re pretty simple to use: just gently brush the surface of the lens until you’ve removed any dust or dirt particles. Make sure to brush around the edges of the lens since that’s where dust is likely to gather. If something still sticks, don’t force it—we’ll deal with it in the next step. An air blower is useful for cleaning off dust in places that are hard to brush. You can use one to clean the front surface of your lens, but they’re most useful for cleaning the back element of the lens—the one that goes inside the camera. If you’re careful changing lenses, you shouldn’t have to clean the rear element very often, but if you occasionally do need to, you may find it hard to properly reach the lens element with a brush. Blowers are a better option in those cases and are also quite simple to use: point the nozzle at the element you’re cleaning and squeeze hard. The air will blow away any particles of dust. One thing: always use a manual blower instead of a can of compressed air. It’s unlikely, but there’s an outside chance that the chemicals and fluids in compressed air could damage the electronics in your camera. Also, the force you get is a lot more than necessary to blow dust off a lens and could eventually damage your camera. It’s definitely a risk not worth taking. While you’re cleaning dust from your lenses, it’s also worth taking your brush or blower to the inside of your lens cap. Dust and dirt can gather there, too, and if you put a dirty lens cap on a clean lens, you might end up with a dirty lens again.
Wipe away smudges and stubborn stuff
Brushes and blowers are great for cleaning off anything that’s easy to remove, but for smudges and stubborn bits of dirt, you’ll need to take a more direct approach. Dry microfiber lens cloths are handy for giving your lens a quick polish when you’re out shooting but, when it comes to removing smudges, they can make things worse and just spread fingerprint grease around. Instead, wet them with a few drops of lens cleaning fluid first, which will dissolve grease and make it easier to remove dirt. You can also get single-use lens wipes that are pre-moistened with cleaning fluid. It’s worth keeping a few in your bag, but as with all single-use items, they’re a bit wasteful. To clean your lens with a cloth or wipe, start in the center and gently circle outward toward the edge of the lens, rubbing away any dirt or smudges. Don’t rub too hard, especially if there are any dust or sand particles—if you’re too aggressive, you could scratch your lens.
Keeping your lenses clean when you shoot
Having nice, pristine lenses sitting at home isn’t much good—you have to go out and use them in the real world. That’s where keeping them clean gets a bit harder. If you’re not planning to shoot immediately and don’t need to be ready to respond to something happening quickly, keep the lens cap on or even put your camera in your bag, especially if it’s dusty, sandy, or wet out. If your lenses are protected from the elements, they’re much more likely to stay clean. If the weather is bad and you want to take a photo, pull out your camera or remove the lens cap until you’re sure of the shot. Frame the image in your mind, get into position, and dial in the exposure settings. When you’re ready, take out your camera, shoot, and put it away again. If you need to, find cover and wipe your lens down with a lens cloth. While not as effective as a proper clean at home, a lens cloth can get the worst of the dust or raindrops off in a few seconds. Though it might be tempting, you should definitely not try to get rid of whatever is on your lens by touching it. Grease from your fingers is really sticky, and without cleaning fluid, the lens cloth won’t be able to do much about it. Don’t change lenses unless you really need to, either. If you’re not careful, it’s an easy way to get dust or smudges on your lenses. Even worse, you can let dust or dirt into your camera or onto the rear element of your lens—both places that are not easy to clean. If you do decide to change lenses, do it somewhere sheltered, put any lens caps on quickly, and keep your camera pointing at the ground, which will stop debris from getting blown into it.
Go shoot
In an ideal world, every lens would remain clean forever, but if you use them, they will get dirty. Don’t overthink things and stress too much. It’s better to mess up a photo because your lens was a little dirty than to not take it at all.