Tips on the logistics of set-up on liveaboard

[sanichols 0]

So, I dive in Northern California and never have condensation problems. I soon will take my new D200 in a DX200 housing (S&S) on an air-conditioned liveaboard in the tropics. What sequence do people use to set-up while avoiding condensation. Should I:

 

1. set-up camera/housing complete in my air-conditioned berth. Go on deck and dive. Rinse, dry, return to air conditioned berth and swap batteries, lenses, ports, etc. Go on deck and dive....

 

or

 

2. take housing and camera onto deck separately and wrap camera in a towel while it warms and then wipe off condensation on housing when it warms. Set it up and dive. Return to berth to swap batteries and then repeat?

 

I don't know... how do you do it?

[MikeVeitch 0]

i always leave my camera on deck all the time, they should have a nice big padded dedicated camera table.

 

leave it in the housing when it is not in use. The only thing i bring back and forth to cabin would be memory card and lenses. For the lenses, to avoid AC issues it is best to bring them onto deck a good 30 mins or more before you need to put it into the housing to let it warm up.

 

Do you have a second body or a second camera for land photos? That would be a good way of not having to bring your UW camera in and out of the room/lounge all the time

[james 0]

Air conditioning is your friend. Cool AC air is dry air. If you can assemble and seal your housing inside AC then this is best. When you bring it outside it will fog on the EXTERIOR of the housing but that's no big deal.

 

If you do have to open stuff outdoors, then warm it up first before exposing it to humid air. Otherwise water will condense on cold surfaces, INCLUDING the inside elements of your lens and camera. Not good. Like Mike says, best to bring them out (sealed in ziploc) for a while to warm up before assembling.

 

HTH

James

[ralphy 1]

Totally agree with James; air con is your friend.

 

The only problems I've encountered have been when opening my housing outside of the air-conned saloon - as in just noticing the lens cap still on whilst preparing to jump in.........

 

...they should have a nice big padded dedicated camera table...

Er yes, should - and one day I hope to find one

[PRC 2]

I am with James also - I have always sealed up my kit in the air con - and don't leave it unattended in the rinse tank - that is a favourite disaster area.

 

Paul C

[sanichols 0]

Thanks for the tips! This was the info that I needed.

 

As for leaving gear on deck.... in PNG I had all of my gear stolen in the middle of the night despite having a crew member sittting on deck as security (we were near Manus Island). I'm hesitant to do that anymore, but this time I'll be in the Bahamas on a 200 ft NOAA vessel, so I'm not particularly concerned about boarders.

 

Thanks again!

 

Scott

[jcclink 8]

Condensation is impacted in part by the ability of the housing to equalize temperature with the surrounding water. Aluminum housings do this very well. Acrylic/polycarbonate not so well. If the internal flash is used alot more heat must be decipated. (This is probably not the case with your D200.) The effectiveness of tropical A/C units is a big unknown for me. How efficiently are they removing moisture ?? I tend to be more worried about them blowing dust around the room than removing water vapor from the air. Since my Nexus housing is aluminum I don't worry about A/C. Doing camera work on deck works fine, as does in a dedicated camera room. For condensation to occur there must be water vapor in the housing & a sufficient temperature differential between the housing & seawater. I tend to minimize this temperature difference vs attempting to minimmize vapor. When moving camera, lenses, flash cards or batteries from A/C room to deck, just give them time to acclimate to new conditions before installing in housing. Whatever works for you I guess. Looks like I'm with Mike on this one.

Edited April 26, 2007 by jcclink

[Iggy 0]

With some measure of reluctance at saying so, I think the notion of assembling your gear in the AC for the purpose of locking dry air into the housing is an idea a bit overcooked Any pro-sumer or better camera and accessories will do fine in a case or on the photo table at the ambient humidity and temperature of the vast majority of dive locations we visit. And if your gear is at ambient you won't experience any condensations issues provided prolonged exposure to direct sun is minimized Personally I avoid keeping my gear in the AC if possible.

[RogerC 4]

Condensation is only impacted by % humidity. If you start with enough moisture in your housing and camera to be at 90% humidity, and the temp drops, you will go to 100% humitidy and you will get condensation. You get condensation on anything that's cold enough to be at the dew point for the local humidity.

 

It's not witchcraft. It's not the sun. Reduce the humidity by starting with air as dry as possible, like the AC cabin air.

 

And protect your $5k camera and $5k vacation with $5.00 worth of dessicant. Why risk it? Why risk even a bit of fog on one dive? get some dessicant.

[james 0]

Maybe I need to write an article about housing fogging. I think it would be a good one as it's a problem on just about every trip I go on. Someone's consumer digicam housing fogs during a dive.

 

This is an easy issue to resolve if you understand the concept of "dewpoint." The dewpoint is the temperature at which water goes from the vapor phase to the liquid phase. It depends on HOW much water is in the air, and the temperature. Condensation inside a housing depends on the dewpoint, and on the thermal conductivity of the housing materials.

 

Why?

 

When you close a housing in 90f moist air (tropical) you're just about at the SVP (saturated vapor pressure). That means that at 90f you are ALMOST at the dewpoint. This is pretty common for the tropics.

 

When you make a dive and the water temp goes down to 75f or 80f then the housing system starts to lose temperature to equalize w/ the surrounding water. Some materials conduct the heat differently, so they cool off faster.

 

Glass conducts heat better underwater than acrylic or lexan, so it cools faster. When the glass cools down to the dewpoint temperature, then ALL of the water vapor in the housing condenses onto the inside of the port glass. :-(

 

The ONLY solution to this problem is to remove the water from the air in some way. One is to use an absorbant medium like silica pack or tampax. The other is to close the housing in dry air (AC) thus trapping air with some water in it that is at a LOWER dewpoint than it will be during the dive.

 

As posted above in the thread, aluminum housings are good because the aluminum cools the fastest. That means that water will condense on the inside of the aluminum housing shell - which is usually not a problem.

 

Cheers

James

[ralphy 1]

Maybe I need to write an article about housing fogging. I think it would be a good one as it's a problem on just about every trip I go on. Someone's consumer digicam housing fogs during a dive.

 

This is an easy issue to resolve if you understand the concept of "dewpoint." The dewpoint is the temperature at which water goes from the vapor phase to the liquid phase. It depends on HOW much water is in the air, and the temperature. Condensation inside a housing depends on the dewpoint, and on the thermal conductivity of the housing materials.

 

Why?

 

When you close a housing in 90f moist air (tropical) you're just about at the SVP (saturated vapor pressure). That means that at 90f you are ALMOST at the dewpoint. This is pretty common for the tropics.

 

When you make a dive and the water temp goes down to 75f or 80f then the housing system starts to lose temperature to equalize w/ the surrounding water. Some materials conduct the heat differently, so they cool off faster.

 

Glass conducts heat better underwater than acrylic or lexan, so it cools faster. When the glass cools down to the dewpoint temperature, then ALL of the water vapor in the housing condenses onto the inside of the port glass. :-(

 

The ONLY solution to this problem is to remove the water from the air in some way. One is to use an absorbant medium like silica pack or tampax. The other is to close the housing in dry air (AC) thus trapping air with some water in it that is at a LOWER dewpoint than it will be during the dive.

 

As posted above in the thread, aluminum housings are good because the aluminum cools the fastest. That means that water will condense on the inside of the aluminum housing shell - which is usually not a problem.

 

Cheers

James

 

James

Thank you for that clear explanation, appreciated by a 'physics' numpty like me!

[Iggy 0]

Reduce the humidity by starting with air as dry as possible, like the AC cabin air.

You guys are going to have every new diver who reads this forum running to their AC'd cabins to assemble and close their housings The dewpoint digression as proof is mostly a red herring. The practical realities of divers the world over for the past decades proves that in this case it's just a bit more minutiae to cloud what is otherwise a simple matter. In temperate or tropical climates and water temps leaving your gear on deck is fine. Hell, even diving Punta Vincente Roca on a blistering hot day with camera gear left and assembled outside is fine. As long as you don't let the sun bake it (whether or not the sun is beating on your gear DOES matter).

 

I'm sorry, and I don't mean to be unkind, but I find the whole assertion that it is necessary to lock AC'd air into your housing, absurd Why make it more difficult or scary than it has to be?

[james 0]

No problem Iggy - you are free to choose where and when you put your housing together. My advice is free and you certainly don't have to follow it. If others choose a different method, then that's fine too.

 

What matters is whatever works best for YOU.

 

Cheers

James

[jcclink 8]

The biggest chance for fogging is for a P/S camera in an acrylic housing, since the onboard flash probably fires for every shot. This constantly produces additional heat in the housing which must be disipated. Get out the silia gel packs for this one.

[Iggy 0]

No problem Iggy - you are free to choose where and when you put your housing together.

That goes without saying, but it wasn't my purpose to point out that I do it differently. Uw-photographers have been leaving gear outside, in cases, on photo tables, on dive decks and out of direct sunlight for at least the 20-some years I have been at it, and now suddenly it's being suggested with authority to assemble gear inside a conditioned area in order to avoid condensation? I grant that it is an option, but my read of your comments indicated something more stringent. This was one of those comments that seemed absurd given the vast experience which proves it unnecessary at almost all locations liveaboards operate.

 

No ill-will intended James. And that's not forum induced gentility, I really mean it

[james 0]

Hi Iggy,

 

I work offshore (10+ years) and have plenty of experience w/ condensation and corrosion. I respectfully disagree that just because something has been done for 20 years does not make it the best way :-)

 

I think it's a legit comment (even from someone with authority) to say that it's better to keep and/or open microelectronics inside in an airconditioned space rather than leaving them on deck.

 

Cheers

James

[davephdv 0]

Interesting

 

I've only had fog issues two times.

 

First in the Bahamas in scorching heat. My mistake I believed was to assemble my housing inside in the air-conditioning. Leaving it outside the rest of the trip (in the shade) I never had a problem. As indeed I never had in any hot environments where I have left it outside.

 

The other was actually in Northern Ca. (Monterey). This was during the beach photo contest. My dome fogged up. Air temp. about 70, water in the low 50s. I resorted to floating on my back on the surface with my housing on my chest. Took the sun about 14 minutes to burn away the fog. Nearby was raft of Sea Otters; some on their backs. Once I got back to shore some guy complained that I had resumed my dive before he maneuver out their to take a photo of this for the contest. He was sure that it would have won the contest and was upset that I didn't stay to pose for him.

 

Does AC actually reduce the humidity by that much?

[jcclink 8]

I would tend to agree that keeping electronics in an A/C environment may be best. But the key word here is "keeping". We as divers do not do that - we're moving our rigs inside, outside, AC, no AC, in the water....

If you let temperature/humidity conditions stabilize you will be alot less likely to have a condensation problem. This means working on deck or in a room at/near ambient temperature. And keep your rig out of direct sun.

Edited April 28, 2007 by jcclink

[JBriggs 0]

Been on numerous live-aboards with both Ikelite and Canon housings and as long as security is not an issue (which it never has been) I leave all camera gear outside on the photo table or shelves underneath. If I have a need to bring some portion of the set-up inside AC'd areas I always take it back out in time to adjust. Had a condensation issue once at Sunset House where I had the housing outside on a table and immediately put the camera inside from the AC'd room. As soon as I saw it I knew what I had done. Outside on the table (shaded area) and covered with a dry towel has worked for me. I have silica packs on hand but have never had to use them.

 

YMMV

 

Jeff

[frogfish 5]

It's rare (and with some trepidation) that I even consider disagreeing with James about anything, but I'm with iggy and jcclink on this one. I do a lot of liveaboard trips in the tropics (and nowhere else), and I see a lot of people having trouble with condensation. Invariably, it seems, this involves housings (usually acrylic, but sometimes aluminum) and other components that have been chilled by being held in an air conditioned cabin. I see people trying to deal with this by sticking bags of silica gel, tampons, and tissues around the housing, muttering imprecations, even prayer. And I tell them, just keep your housing, camera and lenses out of your cabin.

 

At home, my cameras and lenses live in air-conditioned and dehumidified powered dry boxes in a room that is air conditioned most of the time. These are absolutely wonderful if you live in the tropics and don't like fungus growing inside your lenses! On the boat, however, it's a major rule that my cameras, lenses, and housings stay out of heavy cabin air conditioning. (Inside is fine, as long as it isn't an air conditioned space, and I don't leave anything in the sun.) If I need to keep stuff in an a/c cabin, I let it warm to non-a/c room temperature for at least a couple of hours before opening anything up, changing lenses, etc. I've never had trouble with fogging. (I have an aluminum housing by Subal. I don't use silica gel or other dessicants in the housing.)

 

I think I understand the point James is making, but I'm not sure it applies to most liveaboards that I've been on. James seems to be assuming that a/c cabin air is really dry, which simply isn't always the case on a boat. With a damp towel and a couple of wet suits hanging in the room, and water on the floor of an en suite shower/bath, the humidity in an a/c cabin can be at least as high as it outside or in a simply ventilated space, and some times much higher.

 

Frogfish

Edited April 29, 2007 by frogfish

[Iggy 0]

Hi Iggy,

 

I work offshore (10+ years) and have plenty of experience w/ condensation and corrosion. I respectfully disagree that just because something has been done for 20 years does not make it the best way :-)

It's not the best way because it has been done for years and years. It's my chosen way because it works AND it doesn't make the inside conditioned areas of the boat a mass of cameras, housings, cases, tools etc. There is always one or two people who use tables and salons for their gear setup, but if entire boats of photographers begin doing it the results will be unpleasant at best and dangerous at worst. Why am I against the idea of everyone working on their gear inside in the AC? There is a variety of reasons but I will spend time with one example only: recently a liveaboard boat was steered directly into a rock-of-an-island, in a remote location, at 3:30 AM. Had there been cases and gear stacked and stowed in cabins, along the gangway and in the salon, more people would have been injured than were, as passengers tried to exit cabins and make their way to the deck in the sleepy dark of the night. There is a reason captain and crew like photo gear outside, out of the way and/or located in an space described as the photo deck, table or area. And please don't argue that people will store their gear outside and walk each piece, component and/or appropriate tool in and out of the boat as they need them. We both know that won't happen

 

I think it's a legit comment (even from someone with authority) to say that it's better to keep and/or open microelectronics inside in an airconditioned space rather than leaving them on deck.

I never took you for a slickster James! My refernece to "authority" was made because of your certainty rather than any standing you may or may not have in photography, the field of engineering, or academia. That's neither my call nor my judgement to make.

 

I am speaking to you as one photographer to another. And this is a different reason for working on gear inside the cabin than you originally made. But since it is better not to take micro-electronics underwater at all, I consider it a bit dramatic to suggest the cabin greatly reduces the overall risk of damage to the camera and lenses. Plus, you will shortly introduce water to the cabin if you plan on doing all your housing work inside because we both know you can't dry the housing enough to prevent that. And the real exposure is from water on our own housings getting dropped on our cameras and lenses as we re-rig for the next dive. That danger isn't reduced by working on your housing inside.

 

Perhaps it's just me, but I don't follow the process of thought which tries to establish that working on photo gear inside the conditioned areas of the boat is better for the individual as well as his/her fellow passengers. At times it is necessary, at times the light is better, at times the photo table isn't good enough, but those are exceptions. We are all better off on conjested live-aboard boats if most housing and setup work, and storage, is done at the area designated for that work. I am not generally a stickler for rules, but I've been on enough boats and suffered enough close calls to know that some of them really work for the general good.

 

Here's my thought --- if both our methods manage condensation effectively, why muck up the works by choosing or recommending the one that creates additional problems or concerns?

 

That's my last word on this subject. I believe I've beaten the horse well beyond the grave at this point I appreciate the exchange of ideas!

[JBriggs 0]

Not wanting to change the topic... but.... I have long thought, after witnessing, that some people seem to go overboard with prep or maintenance of their rigs. Grease the ring, if required, at the beginning of the trip and then open it (strobe/camera housing) long enough to change the batteries/card and then close it back up after a quick look at the o-ring and the housing. Never had a problem, knock on wood, and it seems sometimes people create problems by over doing it???? Ten minutes after a dive my rig is ready for the next dive whenever it may be. The longer you leave something open or continue to look for something wrong the better chance something will go wrong.

 

YMMV

 

Jeff

[davephdv 0]

What ever you do remember the key rule.

 

If you opened your housing test it in the rinse tank before it goes back in the ocean.