lens fog and Nikon 8073 fog eliminator

[Momo]

Does anyone here have any experience with Nikon's 8073 fog eliminator? I thought I might buy some for my next trip to the zoo. I just want to be sure it's a good product before I buy it... or, if there is a better alternative. (even some sort of home remedy)

Twice now, I have had my 300mm lens instantly fog up on me in the tropical rainforest. The heat is cranked up to "singe" and the humidity is 100% with misters spraying dihydrogen monoxide everywhere. I thought I would get smart this time and beat the humidity. On the drive to the zoo, I turned on the heat and placed my lens where it would be warmed. It took me 10 minutes to buy my annual pass and get to the tropical rainforest. It was too long... instant condensation upon walking into the door. Argh...

So, as I was blowing the lens with my Gioto in a futile attempt to rescue the lens, another photographer witnessed my obvious pain and handed me his "no fog" wipe. My first thought was, "don't muck up the coating on your lens", but I tried it anyway with moderate success. I say moderate because I obviously did not apply the no fog on a dry lens... but was using it to wipe off the condensation. It left behind a bit of funky rainbow swirlies. I have since then given the lens a proper and thorough cleaning.

My best guess, having never used it before, is that it must be similar to Rain-X in that you wipe it on a carefully buff it out.

Reviews, comments, and better ideas welcome. --thanks

[Dave Humphries]

Hi Darren,

I have a UV filter on the front of the lens and even going from a moderately cold English winter's day into a humid tropical greenhouse at Kew Gardens, it only satyed misted for < 5 minutes. I suspect the filter has much less thermal mass than the front element because it is much thinner and the filter acts as 'double glazing'. Also, if you need to wipe because of impatience it is flat and easy and the lens coating isn't at risk because you're not touching it.

Cheers,