Moisture in Lens


TPF Noob!
Jun 16, 2003
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South Korea
Ive been photographing in very humid places lately, and the inside of my lens keeps fogging up. I do everything possible to keep all my equipment dry, but the inside of the lens still gets moisture inside.
Does anybody know what I can do?
I could be wrong, but I was under the impression len's were supposed to be air tight. Moisture leads to mold.
I'm certain Shane is correct, lenses should be sealed but you may want to try keeping the lens in a sealed polybag with a bag of silica gel or similar when you're not using it.
The dessicant will absorb the available moisture so there'll be nothing in the lens to fog when you use it.
Hope this helps.
metroshane said:
I could be wrong, but I was under the impression len's were supposed to be air tight. Moisture leads to mold.

I thought the same thing, so im thinking that the seals in the lens are shot. Im not so concerned with mold...but I am worried about getting spots on the lens glass. Maybe its time for a new lens..
Do you use a filter? I always use a skylight 1A filter and it gets all the moisture and dust before the lens does. Easier to clean and replace if necessary. Also, there might be nothing wrong with the lens, but the camera body seals. Check the seal around the lens mount (unlikely but possible) and around the film door. Silica dissicant (spelling?) bags are always helpful in your camera bag.
I hope this helps.

I think that you will find that most lenses are definitely not air tight otherwise you would run into problems with zoom and focusing actions that extend or retract parts of the lens due to the changes in pressure that would be induced inside the lens by the change in its volume. The better quality lenses may be dust proof but the only way to keep out water vapour would probably be to go for an underwater design, such as one of the Nikonos cameras, where the camera back, controls and lens are sealed with ‘O’ rings and all the moving parts of the lens are within the lens body, ie the front of the lens does not move in and out so there is no change in volume of the lens.
I've never had problems with moisture inside a lens but then I’ve never worked much in extremely high humidity. Keeping the lens and camera in a bag with silica gel should dry them out, and then avoiding opening the camera back, zooming the lens etc as much as possible should cut down the amount of water laden air drawn into the lens and camera. Try to avoid condensation, usually on the outside of the equipment, by not taking the camera and lens directly from a cold environment, such as an air conditioned room, into a warm humid atmosphere. When going from a warm humid environment into a cooler one the moist air in the equipment will chill and cause condensation on the inside of the gear; take the lens off the camera body to minimise this condensation.
If mould is becoming a problem then keeping the lens in a bag with a few drops of a volatile biocide may halt or inhibit mould formation, otherwise it’s off to a repair shop to have the lens stripped down, cleaned and rebuilt.

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