Having spent several decades in the mtns with a view camera, it was inevitable that a few didn't survive or simply wore out. When I traveling into esp rainy areas like the Pacific NW, I pack a mini
dessication chamber - a tight Tupperware box & some tape, with fresh silica gel inside, just in case I
need to emergency-dessicate a lens. It works. Last summer a buddy of mine got a little too carried away photographing up a creek at twilight. We were an entire weeks walk from any road, and way off
trail too. He slipped and sent a couple of very expensive Zeiss lenses into the drink, and busted two legs on his Gitzo CF tripod. None of us had a pr of pliers, so we managed to get his filter threads workable denting them back in position using a soft stick and a rock mallet. One lens cleared enough
by being put in the sun all day, but then the rain came in again, and the humidity fogged it up. It finally
cleared after the trip using my dessication box method. The tripod got two pine sticks duct taped to it.
And the poor photographer himself had to limp out with an injured heel and a 75lb pack over 12000 ft
passes. Life in the fast lane.