Get an air gun to plug into your inflator hose. If you're forced to open your housing on a dive boat or on the shore where its humid to change film, batteries or memory cards, blowing in dry tank air right before latching the housing shut reduces the humidity in the housing.
How to stop the fog up
- Thread starter mattloaf
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H2O Addict
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There is alot of good information here, and I use many of these methods myself. But as a physics major there is a common misunderstanding (I have even seen it on a housing manufacture website) that I want to correct.
The fogging is not due the the humid air being heated up, but actually the opposite. Cooling of the housing underwater is what causes the condensation to form (glass of ice water on a warm summer day).
So turning off your screen will not help prevent fogging, but it will still save battery.
Dave
mattloaf:
The fogging is not due the the humid air being heated up, but actually the opposite. Cooling of the housing underwater is what causes the condensation to form (glass of ice water on a warm summer day).
So turning off your screen will not help prevent fogging, but it will still save battery.
Dave
Fish_Whisperer
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marpacifica:I wear a panty liner in my shorts just in case I run into a Tiger Shark...
I tried that, but when it came time to change it, "ripping it off," was very painful... The adhesive worked better than a bikini waxing. I'm scarred for life....
Cecil
Contributor
Dave I have a degree in Physics and you are wrong about the heat from the LCD. I have done the experiment way to many times, that heat will fog the inside of the housing, on my camera every time. It also does not matter what the water temperature is, I've done the experiment in everything from 37 to 80 degree water. The effect is always the same, leave on the LCD and the camera fogs.
Cecil
Contributor
I just thought about this problem and it all does make sense. The heat from the camera heats the air in the housing and the cold housing cause the condensation. It makes perfect sense.
H2O Addict
Registered
Let me try to explane it more.
When you seal your housing you trap a specific amount of air inside. That air contains a specific amount of water vapor that will not change throughout the dive (unless you use a dessicant to trap the water vapor). The air you sealed inside had a specific temperature and relative humidity. As the temperature decreases the relative humidity increases until the dewpoint is reached and condensation forms. Heating the air decreases the relative himidity, but it will have little affect on fogging because it won't heat the housing walls (too much water cooling them) where most condensation forms.
Dave
When you seal your housing you trap a specific amount of air inside. That air contains a specific amount of water vapor that will not change throughout the dive (unless you use a dessicant to trap the water vapor). The air you sealed inside had a specific temperature and relative humidity. As the temperature decreases the relative humidity increases until the dewpoint is reached and condensation forms. Heating the air decreases the relative himidity, but it will have little affect on fogging because it won't heat the housing walls (too much water cooling them) where most condensation forms.
Dave
Cecil
Contributor
Dave, regardless of the theory (which I am not dimissing), I have seen this to many times and the amount of condesation is proportional to the amount of time the camera is on.
There is another source of humidity that is being ignored, namely the water in the camera. All those circuit boards can hold a lot of moisture. When the camera heats up, this moisture is forced into the air and condenses on the cold housing.
There is another source of humidity that is being ignored, namely the water in the camera. All those circuit boards can hold a lot of moisture. When the camera heats up, this moisture is forced into the air and condenses on the cold housing.
f3nikon
Guest
Cecil:
Correct!
Because you can test that theory by taking the camera housing down without the camera, you will get NO fog. The heat generated from the camera is what is turning the condensed water,sticking on the walls, into steam then sticking to the cold glass of the housing ports.
Best thing to do before leaving for the dive is to blow dry the housing (low heat) and camera with an hair dryer to burn most of the water off. And you can leave the camera's LCD on for a few minutes before placing it in the housing (attached to the power cord to save the batteries), but still blow dry the housing.
Because once you remove the water and close the housing door where else are you going to get your source of water to generate the steam?...unless you have a very small leak some where, letting the sea water in. Now thats another bigger problem.
f3nikon
Guest
H2O Addict:
Actually it's INCREASING the temperature that makes the steam or humidity like in the hot tropics. Cooling the air condenses the water back to liquid or even solid ice or snow.
"fogging" is from the heat generated by the camera turning the water droplets into steam which then sticks to the cold housing ports due to the colder outside ocean temp. Keep the water out in the first place and you fixed your problem, you will also make you camera live longer by keeping it dry. The water in the camera when in the tropics is not good for the electronics.
Try a product called "Gloop" available at motorcycles stores, works a treat for Visors on your helmet, Im sure it mest be good for camera cases
