Despite how well we try to protect our filters, dust, dirt and smudges happen. When it does it is important that your method to clean them doesn’t make things worse. This article is devoted to the three different methods I personally use to clean my filters, and lenses. But first, remember, an ounce of prevention is worth a pound of cure. You’ll need to clean your filters less if you take steps to prevent them from getting dirty in the first place. Don’t leave them out to gather dust. Don’t handle after eating greasy food. Hold by filter ring so the oils from your fingers never touch the glass. And store when not in use. Personally, I keep my circular filters in a Tamrac filter case, my Grad-filters in a Adorama Slinger, and each filter is always in a designated position so I can find what I need even with my eyes close – see article.
Method 1: Lens Cloth and Your Breath. This is simplicity itself. Exhale from your mouth directly onto the filter to fog them up. Then, using a clean, decent size, good quality, micro-fiber lens cloth, wipe clean (wipe, don’t rub). This method will remove most smudges and the moisture from your breath is already filtered and clean.
Method 2: Lens Pen. If you don’t own one of these get one. Any brand will do since from what I understand they are all exactly the same just labeled differently so don’t waste much time or money shopping for a name brand. The lens pen is an extremely useful tool that does two things. At one end there is a soft brush for sweeping away the dust that always seems to find its way onto the glass. The other end of the pen is capped with a carbon-black cleaning material. Twist the cap then pull it off to refresh the cleaning material on the tip. Then use that end of the lens pen to wipe off stubborn smudges. It is an amazing little tool that works. Just remember to replace it about once a year. I own several, one in each bag and never go shooting without one.
Method 3: Formula MC. Over 90% of the time the first two methods will do the job. The other 10% of the time these methods will simply not be enough to remove stubborn smudges. In particular, many people complain that certain brand multi-coated filters like Hoya can be next to imposable to get clean. The solution is Formula MC. Better yet, the Formula MC kit from www.2filter.com which I use. From their website, “Conventional lens cleaners can not properly clean the unique coatings on multi-coated camera filters and camera lenses and a chemical smear can result. When this happens, it looks like the camera filter is getting worse as you try to clean it.” The way I use it is to hold the spray bottle away from the filter and then spray directly on the filter. Then, I take the lens cloth and simply wipe clean. (Caution. If you are using this to clean your lens do not spray directly onto the element. Instead, spray on the cloth and then wipe. You do not want liquid seeping into the lens.) This kit is my bag for all trips and it is the best cleaning solution I have ever used and a must for getting smears off many multi-coated filters. Also, you will find some of the best prices on filters (sometimes the best price is visible only after the item is added to the cart), along with free shipping on orders over $66, when you buy from The Filter Connection.
I recommend the above methods because this is what I do and it works, plain and simple. I also use the same methods for cleaning my lenses - except I never spray Formula MC directly on the lens. To see more of my articles on filters just click here.