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More than you ever wanted to know about lens cleaning:

Get a face powder brush from a cosmetic department - the kind that is a sable type brush that retracts into a little tube like a lipstick and has a cap like a lipstick. These are great for dust on the lens and the retract feature keeps the brush from being contaminated by anything that will transfer to the lens. Your wife can help you find one of these. Of course, get a brand new one and use it on nothing but lenses.

You also need Kodak lens cleaning tissue and lens cleaner, preferably Kodak. I like Kodak's tissues because they come in an envelope with an inner cover so that you can keep them really clean. Always keep the pack closed up unless you are getting a piece out. Don't use any cleaners or tissues designed for eyeglasses. These have silicone (even impregnated in the tissue or cleaning cloth) which is designed to fill in microscopic scratches in glasses thus reducing refractive distortions. Trouble is, the silicone attacks the coatings on photographic lenses which reduce internal reflection and and enhance various properties. If you wipe an eyeglass cloth on a camera lens, it will make a horrible mess of it. By the way, if you fingerprint a lens, clean it right away. The oils from your finger will also attack the coatings if left there too long. Anyway, the good stuff is available at any camera store or probably K-Mart photo dept.

First, brush off any loose dust or dirt with the brush. Then, wad up a piece of lens tissue, trying your best not to touch the part that will touch the lens. Put one drop of lens cleaner on the wadded tissue. It usually comes out in kind of a big drop. Then shake the wad so excess cleaner goes on the floor. If you use too much cleaner, it can run around the edge of the objective lens element and seep through the mounting around to the back side. In some lenses, elements are sandwiched together. If fluid gets in there, it will spread by capillary action and look like an ameba in your lens. Then you really have a big problem. Send it in to the factory to be taken apart.

Okay, you've got the right amount of fluid to just dampen the tissue. Rub it around the face of the lens and it will clean off oils and water droplet residue from rain or whatever other crud is on there. But you will still see a bit of residue from the cleaner if you look at the glass with some light reflecting off it like a back light - which is a very good idea for the whole process so you can see what you are doing. Now take another piece of fresh lens tissue, wad it and leave it dry. Use it to polish the surface of the lens and rub off the residue from the cleaner. If there is any lint or specs left on the glass, use the brush one more time. Unless your coatings have been damaged, this should leave you with a sparkling clean lens. Repeat the procedure on the front and rear elements of your wide angle adapter as well. It's particularly important to keep the front element of your wide angle clean as stuff on it will almost be in focus at small aperture settings.

On a related point, somehow when I was in Papua New Guinea, I got a speck inside my wide angle adapter. There is no way for me to get it out, I will have to send it in to be disassembled. I will probably never do this, however, since I need it all the time and can get by with rotating the lens in the screw mount so the speck is out of frame at the bottom. At wide aperture settings it can't be seen.