[PDL]

I think you might have to chalk it up to experience. Next time you go to Mono lake put a UV filter on the lens, then the spray will not get on the lens. Anytime you are going to a place with spray, it is a safe bet to put on a filter. I have been at the beach (Southern California) where the on-shore wind spray literally coated my glasses with a layer of salt. While it was wet, it was easy to clean off, but in the car it dried quickly. My brother did not clean his glasses right away and hit them with a glasses cleaning paper resulting in scratches. Always clean your lenses if you think there is salt or some other "grit" on them, especially if it comes from water or spray of some sort. Clean the lens while it is wet, once it dries it is basically sandpaper.

As for UV filters causing image degradation (only visible at 400%) what little effect is nothing compared to the image degradation caused by having mineral crystals form on the lens surface. I remember back in the film days when going to Yellowstone National Park, there were warnings around the geyser basins about getting the "steam" and droplets on your lenses. The chemical composition would eat the coatings off. But back in the film days, anyone not using a 1A or UV filter at 7K feet was really not paying attention.

Full disclosure: I was raised in Wyoming and put a UV or 1A filter on all of my lenses because UV haze was a real issue at "normal" Wyoming altitude - around 4K on average if I remember correctly. Most of the times I spent shooting in those days was in the mountains at 8-10K feet in elevation.

[flyingfishfinger]

Yeah, learned the hard way I guess... brand new lens too

And I meant what about image degradation from having the damaged coating sections on the front element, not from the UV filters...

R