Lens Cleaning Tips
When shooting video or taking photos a clean lenses and filters are a must. Rather you shoot digital or on film, or have consumer or pro camera, you are not immune to the dirty forces of nature. I can tell you, little is more disheartening than coming home from a shoot and finding your images are corrupted by a dirty lens. There is no remedy for this foolish, yet easily avoidable mistake. You can not rely on the view finder or LCD screen, the resolution is just not good enough to show most small smudges.
What is worse than a dirty lens you might ask? Well it is improper or obsessive over cleaning of the lens. Most of the lenses we deal with have a special coating on them which helps reduce flares, or light reflected by the surface of the lens. In addition the coating allows in more light than an uncoated lens. Typically on a glass to air surface 4% of light is naturally reflected away. A coating can bring this level down to about 1%. Lens coatings can usually be noticed by their red-purple or green appearance. Lens coatings can be rubbed away from over cleaning and applying too much pressure on the lens as you clean.
The number one way to have a clean lens is using preventative measures.
- Always use lens caps when not shooting.
- Keep your fingers off the lens.
- Use caution when changing lenses.
Use extra vigilance when shooting outdoors. Dust can come from a plethora of sources. Be especially aware around pollinating trees, salt water, and sandy areas with a lot of wind. For example during our recent vacation in Tunisia, we stopped to take photos at some sand dunes. I step out of the vehicle with my camera in hand ready to take a shot and was immediately blasted by a whirlwind of sand.
Simple dust particles: A little dust on the lens doesn’t really hurt a lot, as the end of the lens will be out of the focal depth of field. Problems could arise though when shooting against a strong light source, where reflections off the dust can intrude. Dust particles can be easily removed with a light brush or air. Avoid using any kind of compressed air cleaners, which could leave a residue on the lens surface. The essential and primary tool for the job is a bulb type air blower. It is simple and easy to use, just avoid contact with the tip of the blower and the lens as to not scratch the lens surface.
For more aggravating dust use a fine brush to gently knock off particles. A great tool that should be in everyone’s equipment bag is a brush style lens pen. They offer a quick and easy method for dust removal as well as other deposits on the lens. One end of the pen will have a retractable brush, the other will have a non liquid based cleaning pad. These gizmos have become extremely popular and are in wide use around the world.
First use the brush tool to remove all abrasive deposits then use the cleaning pad lightly in a circular motion. These pens are usually marketed to clean both lenses and LCDs. I recommend having a different pin for each use. Also these pens can not be cleaned and will have to be replaced from time to time, which is no problem considering how cheap they are. Similar type pens are also used for sensor cleaning, which I will cover in a future post.
Liquid Based Cleaning
Liquid based cleaning methods have long been the standard method and are necessary for stains like grease from your fingers. Apart from the liquid a cloth is also required. Avoid cheap dime store wipes that may be too abrasive. Use a good microfiber cloth specially made for lens cleaning. Before attempting to clean your lens with a liquid and cloth, use a brush to knock off any dust particles. One of the best liquids you can use is your own breath. It contains no chemicals that may eat away at the coating on the the lens. Breath hard on the lens surface leaving a fog of moisture on it. Then using a the microfiber cloth, gently wipe in a circular motion from the center of the lens to the outside(without rubbing). In other words, leave off the elbow grease. If a problem area still exist a stronger cleaning solution will be needed.
Many products exist for lens cleaning. It is important to chose one that will leave no residue on the lens surface, such as those commonly sold for eyeglasses cleaning. One possible solution is pre-moistened cleaning pads especially designed for camera lenses. Use these pads one time and dispose off, they should not be recycled. Your other option is to use a cleaning liquid in conjunction with a dry cloth. The procedure here is the same, just be aware that it only takes a little bit of liquid. A small amount will go a long way and decrease the possibility of leaving any kind of residue on the lens surface.
A full line of top quality cleaning products can be found at the B&H photo and video store. Keeping your lens clean and dust free is one of the most essential parts of coming home from a shoot with usable material. Make a habit of checking your lenses before shooting and periodically throughout. With a little care and proper handling, your lenses can give you years of beneficial service.