Quote Originally Posted by eddym View Post
Not much. Again, at temperatures over 80F and humidity over 50%, it doesn't take long for fungus to begin to attack the glass. If you catch it early, you may be able to have it cleaned fairly successfully. But once it etches the glass, there's nothing you can do. I lost some nice lenses to fungus before I got my dehumidifier.
Ummmmm.....don't tell that to all the lenses sitting in this coastal Florida house for 49 years. From a 1944 Leica to a 1950's Rollei to cheap cameras to mid-level SLR lenses. I've never seen it.

Fungus attacks, if it does at all, the glue between the elements. I think manufacturers have had that licked for years. I don't know how they do it, but I know that a wee bit of mercury will stop fungus cold. That's how they used to stop paint from mildewing back when.