Flood a housing with gaseous nitrogen

[Blueskys4ever]

Has anyone ever considered flooding a camera housing with gaseous nitrogen?

The idea is to replace the ambient air that has moisture and will compress.

Since GN is very dry, I would think this would cure fogging.

Since GN does not compress well, it would serve to strengthen the housing.

 

[wedivebc]

Has anyone ever considered flooding a camera housing with gaseous nitrogen?

The idea is to replace the ambient air that has moisture and will compress.

Since GN is very dry, I would think this would cure fogging.

Since GN does not compress well, it would serve to strengthen the housing.

You a tire salesman by any chance? Where does this compressability thing come from? Air is 79% nitrogen.

 

[fppf]

yeah it will solve fogging issues because it has almost no moisture content.

But, yeah, its compressability is just about the same as air.

Just go to a hearing aid store and ask them for a jar of hearing aid drier, its a molecular sieve that sucks moisture out of the air. Put your housing together the night before with that in there and no worries. Plus its reusable, when the indicating beeds go white, through it in the oven for 30 minutes and your good to go.

 

[bleeb]

Since GN is very dry, I would think this would cure fogging.

True nitrogen from a tank is dry, but so is air from a scuba tank, and both for the same reason: They've been dried before being put in the tank (ignoring things that aren't suppose to happen, like wet fills and broken dehydrators.)

Since GN does not compress well, it would serve to strengthen the housing.

Did someone revoke the laws of physics?
Gaseous nitrogen compresses just fine. In a way, not surprising, since air is 78% nitrogen.

Now liquid nitrogen, on the other hand, doesn't compress much. Of course, there are a whole bunch of different issues with LN2...

 

[Charlie99]

True nitrogen from a tank is dry, but so is air from a scuba tank, ........

Scuba air has a dewpoint of something like -40C/-40F IIRC. So if it weren't a case of a solution looking for a problem, purging a bunch of air through the housing would leave it nice and dry.

If you had both a fill and an exit port, it wouldn't need any more pressure than what you would get from shoving a big funnel over a reg mouthpiece and then purging a bit.

Of course, you now have two more ports that can leak at depth, so IMO it's a net loss.

 

[bleeb]

Scuba air has a dewpoint of something like -40C/-40F IIRC.

CGA Grade E: 24 ppm / -65F
mil-spec Aviators Breathing Oxygen: 7 ppm / -81F

Courtesy of: Fill Express -- Quality of Breathing Gases

 

[fppf]

Geez just use a desiccant pack, I dive the great white north.
In the summer its 90 degrees with 100% humidity, the water is 40 degrees.
The lowest you ever need to get the dew point to is 27 degrees.

 

[gert7to3]

I have had fogging problems on a few dives. We kicked the idea of tank air around a few months ago. I have positioned my housing in front of a tank valve, slightly opened, as I inserted the camera. One could also put a camera and housing in a clear plastic bag and inflate it with tank air before closing it up.

Now comes the question over whether this should be done with nitrox? The increased oxygen content might cause problems with lubricants or hot parts.

 

[Diver Dennis]

The dry air from your air conditioned room will work fine as well but I've changed lenses and ports on dive boats before and still no fogging...

 

[herman]

I had had fogging problems with my 5050 until I started using the room A/C to fill the housing with dry air. Just before closing the housing I crank the A/C down to make sure the compressor is running and hold the housing and camera in front of the air stream for several minutes. This drys out any moisture in the camera and fills the housing with reasonably dry air. While still in the air stream I close the housing. I never open a housing outside of a room if at all possible so this works very well for me.