Quote Originally Posted by summicron1 View Post
any glasses shop sells lens cleaning fluid -- and usually has some sort of tissue -- if not any piece of clean much-washed lint free cotton cloth will do fine. To be brutally honest, i clean my leica lenses with windex on a tissue and call it good. wipe very gently, no scratches yet.

microfiber clothes are also very good.
Some of the products a glasses shop carries for cleaning may contain silicone or similar which aids in hiding minor scratches and scuffs on plastic and glass lenses. If used on a camera lens it will leave film that may affect optical quality.

I'm a long time user of Kodak lens cleaning fluid and tissue, but ran across a thread in a forum where some people are using Heet dry gas to clean lenses and digital sensors which is an isopropyl/menthanol based alcohol containing little water. I have tried it on a couple of older lenses and filters and it seemed to work well and does not leave any residue. I haven't braved up enough to try it on any of my good lenses. Curious if any one else has heard of this and may use it routinely.