Silica Gel Usage

[Digger54]

I know what the silica gel does, I use some larger "rechargable" packets of it in a gun safe at home, but I am unsure of how to best apply it in underwater photography.

Do most keep silica gel in the housing during a dive?

Where do you put it in the housing? I might have enough space between the tray and housing bottom if the packet is thin and small enough.

What do you do to avoid it moving and interfering with the operation of controls?

Is it likely to produce any dust if it flops around in the housing that could coat a lens and reduce the sharpness of photos?

Thanks

 

[joewr]

Hi, Digger,

Hmmm, I have never even thought of using silica gel in my housing. I do not think it will do much good if you have a flood: there will just be too much water for it to absorb. What it is used for is removing the water molecules in the gaseous state that is in the air. And that ain't much, normally.

I guess I would not put anything extra in my housing. One more thing to go wrong. Imagine...just as the whale shark swims by, the silica gel bag breaks and your lens is looking at a Saharan sandstorm...

Just my drift....

joewr

 

[Diver Dennis]

Some cameras heat up in the housing and cause condensation. Gel packs help mitigate the effect.

 

[joewr]

Some cameras heat up in the housing and cause condensation. Gel packs help mitigate the effect.

Hi, Dennis,

More water molecules can be in the gas phase as temperature rises, so I am a little puzzled by what you wrote. I would think that it more likely that as the housing cools, any water vapor would condense. It does this on your dive mask.

However, I have never had condensation on the glass of my camera housing and have assumed that it was because unlike my face, there was very little water/water vapor on my camera.

joewr

 

[Cacia]

hmmm. I put my camera together in an airconditioned hotel room, then when I walk outside in the warmer climate, my inside of the housing fogs.

 

[Diver Dennis]

Hi, Dennis,

More water molecules can be in the gas phase as temperature rises, so I am a little puzzled by what you wrote. I would think that it more likely that as the housing cools, any water vapor would condense. It does this on your dive mask.

However, I have never had condensation on the glass of my camera housing and have assumed that it was because unlike my face, there was very little water/water vapor on my camera.

joewr

I've seen in the tropics where a camera heated up after about 70 shots, causing condensation inside the case in the cooler water. Gel packs, from Kevin Davidson by the way Catherine, solved the problem.

 

[joewr]

hmmm. I put my camera together in an airconditioned hotel room, then when I walk outside in the warmer climate, my inside of the housing fogs.

Hi, Catherine,

I have had my sunglasses fog up on a summer day in Houston when I walked outside from an air conditioned building. However, the glasses were cold and the air was humid.

I have left our frigid, air conditioned condo in Hawaii on hot, humid days and never had that problem with my housing. Do I sound puzzled? Yep!

Chemistry tells us that there is more water vapor in hot air than in cold...that is one of the reasons it rains...and one of the reasons steam condenses when it cools...

hmmmm.....

joewr

 

[joewr]

I've seen in the tropics where a camera heated up after about 70 shots, causing condensation inside the case in the cooler water. Gel packs, from Kevin Davidson by the way Catherine, solved the problem.

Hi, Dennis,

Does a camera only heat up in the tropics? And why does it heat up? Are these cameras SLR's or point and shoot? Are they film or digital?

This is really interesting to me because there is so little current generated when a camera works that I have hard time imagining that the associated electrical resistance can cause such heating.

I would like to be educated as to what the root cause is....

Interesting, folks, very interesting...

joewr

 

[Diver Dennis]

The battery heats up the surrounding air. Point and shoot, an Oly I think. Kevin Davidson the Photo Pro at Sam's Tours in Palau told us about it.

 

[HowardE]

Yeah... P&S cameras heat up more than DSLR cameras. I keep a silica gel pack in Michelle's Canon S70 (we've had fogging issues even when loaded in a room with AC) - but I've never had a fogging issue with my D200, and I don't always load it in an air conditioned room.

I think a good part of the issue with P&S cameras is from the internal flash as well.