Help me before I get another camera killed!

[flareside]

Take it from cold dehumidified air to warm humid air and you will get condensation on all surfaces - inside and out. The inside will be less, as the volume of air it is exposed to is less, but it is still there. To be avoided.

The only caveat to this is where the outside environment is warm and humid and the water you will be diving in is cold. Then I would want to take the camera out of the housing in AC and put it back together in the same environment.

Actually you kind of contradict yourself there. If you seal a camera housing in an air conditioned environment and take it outside, the only condensation that will occur, occurs on the outside of the housing as the air inside the housing is dry.

But as Lwang didn't exactly explain it correctly, lets go back to basic AC theory. When warm moist air hits a surface that is colder than the condensation point of the warm moist air, the moisture in the air condenses on the cold surface. The reason this is relative to AC is that in the AC unit, the warm moist air passes across a cold cooling coil and the moisture clings to the coil (and ultimately collects and drains out the bottom of the unit). Thus, the air that comes from the unit is not only colder but inherently dryer. After several passes, it is considerably dryer. That is why it is best to seal the camera inside an enclosed, air-conditioned space. Why this is relevant to camera housings if if you seal warm moist air in a housing and the water cools the surface temp of the housing to below the condensation point, the inside surface of the housing fogs. While this can also happen to housings that were sealed in an AC environment, it a lot harder because the surface temp has to drop a lot further to achieve condensation of the dryer air.

So the basic rules of thumb are seal it up in AC when possible and if you are out on a boat where it is not possible, use a blast of tank air to fill the housing with dry air prior to closing. Otherwise use dessicants whenever you have to close it in a hot humid environment.

 

[Darnold9999]

You are completely right.

As long as the camera is in the housing in AC and sealed in AC you are fine. The problem is when you play with the camera in AC and take it out to the deck to put it in the housing.

 

[NautilusCairns]

Wow, crazy. I have been using acrylic housings forever with zero problems.

Fogging is a humidity problem. You shouldn't have this too much on your trip as you won't be going from AC to humid outside air it sounds like. Moisture munchers can't hurt.

I don't take my oring out very often unless it really needs it. One advantage of the acrylic housings is you can see what's on your oring.

Up your inspections - it sounds very much like teensy bits of water have gotten in where they shouldn't have. You might not even notice a "leak" like this but it's just as damaging in the long term. Make sure you have a bright light to work with when inspecting your orings and be ruthless removing the tiniest specks. Remember to check your grooves before inserting orings and before closing the housing. I can't tell you how many divers I have seen spend 15 minutes inspecting the oring but not even glancing at the big wad of sand or hair on the groove of the housing!

Bring a collapsible esky/cooler bag for the boat and surface intervals, pop the kit in there and make sure it's not laying around in the sun. Not only will the cooler help not bake the camera but it offers a bit of padding protection and can be used as a portable rinse tank, too.

I too must be fortunate in respect to camera housing fogging, both with my earlier Ikelite for the A640 (the big boxy one) and my current Recsea S95. I do use moisture munchers which I dry out in the micrwave periodically but I haven'y worried about the AC/non AC environment as often you don't have a choice. I have oberved that most of the fogging incidentys encountered by my friends have been with compact plastic housings.

I am also a firm believer in the collapsable eskie/cooler idea and I pack one when travelling . I have had to get a bigger one lately as the size of my rig increased with a second strobe. The cooler does all that Alcina mentioned as well as allowing you to avoid the dreaded communinal rinse tank where my only housing damage occurred (twice)

 

[drafahl]

The number one problem we see on all our dive trips with fogging in clear housings can be traced back to leaving a clear housing in the sun. Even if it is only for a matter of seconds, the sun heats the air in the housing, causing fog. ALWAYS put a wet towel over your clear housing when getting into the sun - especially when getting into a smaller boat. Wet the towel because it keeps the housing cooler and it doesn't fly away when motoring to your site.

Jack and Sue Drafahl

 

[gert7to3]

I strongly agree with the sentiments of handling and closing one's camera housing in an A/C environment and shielding your housing from the sun. I will also go one step further and blow tank air into the housing before closing it. I do this with an old Spare Air adapter to which I attached a length of plastic hose. I don't blast the housing with air, but I do liberally flush it for about 30-40 seconds. This is an excellent option if one needs to open a camera housing in a warm humid environment, such as a battery change on a boat.

 

[blibecap]

There is a lot of talk here about flogging and humidity in the camera housing but, do you really think that was the cause for Killing your camera? or do you think you had a leak somewhere? There is a lot of good advice here but seems like it is a little off track from the subject.