Cleaning External Glass (Ports, Diopter, etc.)

Just finishing up a trip to Indonesia. While packing up my gear, I noticed a film on all my external glass. The water in Ambon was pretty scummy. I'm looking for suggestions to clean the glass without messing up any coatings that may be on the glass, particularly my CMC.

Thanks,

Bob W

I think that I would try "lens cleaner" as used for microscope lenses. I haven't really looked, but I suspect that there is something similar, if not the same, that the lens manufacturers suggest and approve. The big thing to be aware of is, if there is a chance of any grit being trapped in the film, don't wipe with any pressure or you will scratch the lens. Use the cleaner to dissolve the film, and then gently remove it using a lint-free, diatomaceous-earth-free wipe, such as lens paper. Many types of paper are actually fairly abrasive, so you will want to be careful removing the film.