Best time to put camera in housing?

[annie]

I lost the anti fogging solution I got from Canon quite early on. For a while I tried the silica packs, they really didn't work for me.

>>the cause of fogging is the moisture (in the air) trapped in the housing and not so much the temperature.<<

sorry to disagree - I think it's the temperature - the camera heats up the housing and together with the colder water it causes condensation on the inside just like on windows in a house. Why it's only on the lens port I don't know.

>>Consider that the humidity in Thailand is generally quite high, I never really had any problem with fogging. . .So far the air temp is generally over 30C and water temp has never dropped below 27-28C here.<<

Again I think it's the temperature difference causing fog which is why you don't have any.

 

[Groundhog246]

annie once bubbled...
condensation on the inside just like on windows in a house. Why it's only on the lens port I don't know.

I do. The lens port is optical quality glass, the rest of the housing is plastic. Glass conducts heat much better than plastic. Thus the inside of the lens port, cools faster than the rest of the housing and attracts the relatively small amount of moisture present. Thus it fogs and the rest stays nice.

 

[annie]

This is such a great forum

 

[mmakay]

>>the cause of fogging is the moisture (in the air) trapped in the housing and not so much the temperature.<<

sorry to disagree - I think it's the temperature - the camera heats up the housing and together with the colder water it causes condensation on the inside just like on windows in a house.

You're both right ....

If the air was 0% humid, there would never be any fog, even if the air in the case were 100 degrees hotter than the port glass . Likewise, if the contents of your housing were always the same temperature as the water, even 98% humidity would not cause any fog. Unfortunatly, when diving, there is always humidity and when shooting digital there is always a temperature differance.

Turning off the LCD helps because the camera stays cooler. Moisture trapped in the camera evaperates because of the heat and ends up on the port. A good desecant will help that, but it can take time, and the desecant needs to be very fresh.

Closing the housing in your hotel room helps because there is less moisture in the air and less moisture in the camera. That means the temperature differance has to be quite a bit greater to reach the dew point. (Everybody remembers their phase charts from chem class, right?)

Canons suffer from this problem more than most because the volume of the case is so small (less air for the moisture to live in, so it finds a new home) and the cameras run hotter than average (so the temperature differential is much greater). It's one of the reasons my S30 will no longer dive with me, and I bought a Nikon.

-Mickey

 

[clive francis]

before you get in the water

 

[ReyeR]

You're both right ... and wrong.

thanks Mickey for explaining that, I should have done so with my post. Annie, when I said 'and not so much the temperature' it was more in context with sean00xj's question ie 'when i'm in the 72 degree hotel room'. Hope Mickey's post makes it very clear on why cameras fog underwater. I'd also like to stress on the word 'fresh' re: desicants. If the silica gel has been sitting exposed to the ambient humidity then it will not help at all when inside the housing.

 

[jray]

I put my s45 in it's housing in my hotel room just before I leave for the dive boat. I put a few fresh moisture munchers in with it and have never had a problem with fogging. I've done about 10 dives this way. Now if I could only find a battery that would last thru 2 dives + surface interval. The battery always seems to die on me about half way into the second dive leaving me with a useless floating brick to lug around. Have you ever noticed the coolest fish show up when the camera is out of juice?

 

[ReyeR]

Canons suffer from this problem more than most because the volume of the case is so small (less air for the moisture to live in, so it finds a new home) and the cameras run hotter than average (so the temperature differential is much greater).

and

Now if I could only find a battery that would last thru 2 dives + surface interval.

Some of the reasons why I luuv my C5050 / PT015 combo. Inexpensive housing with enough volume and lots of space to put plenty of silica gel - and yet not too big and clunky. And batteries run for 2+ dives with plenty of juice to spare to view, delete and copy during the surface interval . Perfect!

 

[MacHeath]

What we really need is a camera that can be inductively charged (like a toothbrush), with a WiFi connection to download the photos. No need to open the casing at all, so no problems with condensation/dirt etc.

 

[jray]

I like the way your thinking. Now how am I going to get my laptop and generator on the dive boat?