Canon 20mm fogging

[marcin 0]

Just bought the Canon's fix 20 mm lens for my 20D. Tried it last week. Was told by a guy that he had moisture problems in the center with his lenses.

Turns out all my pictures on that boogie had the same problem - spot in the center that pretty much ruins the photo. Frustrating. It was quite humid, but my 15 mm Canon lens never did that to me.

Any experience with this lens? Should I be selling it to some ground attached photographer?

[Deuce 1]

I think that's just the cost of doing business where it's humid. I have a Canon 20 and a Sigma aspehrical 14. Never any problems with either here in California, but in Sweden the 14 fogged up every jump, just about. Really a pisser, cause I got that lens specifically to get exit shots out of the Herc. It was OK for the exits, but fogged up about halfway through the dive.

[billo 0]

marcin, i've got the same 20d/20mm setup that i use for most tandem/work jumps. only times i've had problems have been on extremely humid days, and it typically doesn't occur till right near pull time for tandems or shortly afterwards. by the time i shoot landings, the moisture is gone. what conditions and what discipline are you shooting? The canon 20mm is a sweet lens, that would suck for you to part with it.

[marcin 0]

It was an atmonauti boogie in France. I was shooting big ways, staying a lot in the air, since vertical speed of an atmo group is very low. It was the first time I used this lens and unfortunately I did not try my other lenses to compare.

There were showers all the time and it was indeed humid and on times cloudy. It basically fogged up right after the exit.

I'll be in Arezzo and Eloy in Nov/December weather there should be pretty dry. Maybe it will work there.

I mean, if its not a problem specific to this lens, then its OK. It was just this warning from another experienced jumper, that his 20 mm had the same issue (not on the same boogie).

[AndyMan 7]

Fogging at the end of the skydive on humid days is normal with pretty much any lens. The fog should go away as the lens readjusts to the new warm ground temperature. This fog is caused by warm humid air condensing on the outside of the cold glass.

It sounds like you're describing something else. It sounds like your fog isn't going away at all, that it's always there. This indicates that something else is happening - my guess is that you've gotten some humidity inside the lens somehow. Lenses are suposed to be sealed, so that shouldn't be happening.

One trick I learned a few years ago is to periodically place your lenses into a vacuum to suck out any moisture from where it shouldn't be. The rigger I learned this trick from used a FXC test chamber that used to be quite common on dropzones. He'd leave his lenses in the chamber for about 10 minutes.

_Am

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You put the fun in "funnel" - craichead.