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Lights In Water

Published : 12th August 2004


The question is :

>>> Although I have never seen this done I've been told that you can immerse a light in water, an open face or even a fresnel, I presume, and THEN turn it on and it will burn quite nicely >>>

I've put a 1K Molequartz Molepar in swimming pool and turned it on, it worked just fine. We put some shade of a blue/green gel on and it looked beautiful. The gaffer I was working for said he'd done it before with half a dozen lights in one pool, so we did what the boss said. We did however give him the honour of plugging the submerged light in. After all was said and done, it worked perfectly; the water wasn't hot and nothing shorted out.

Nate Yolles
http://www.nateyolles.com



>I've put a 1K Molequartz Molepar in swimming pool and turned it on, it >worked just fine. The gaffer I was working for said he'd done it before >with half a dozen lights in one pool

Were they powered with AC or DC? My understanding is that this can only be done with DC. Or, if it can be done with AC then the difference is that only with DC could you safely have people in the pool as well.

This relates to AC and DC generators and how one, DC, is inherently "safer" then the other.

Edwin Myers



I've put a 1K Molequartz Molepar in swimming pool and turned it on, it worked just fine.

I believe the reason no one has commented on this post is that it is just so goddam idiotic. It rates with the morons who get those Darwin Awards for the most stupid way to kill yourself. Of course the lamp will work, why wouldn't it... but you are relying on the A.C. having a lower conduction path active to neutral through the globe and the water having a greater conduction path active to earth (ground). You are relying on the water to insulate you.

This is about as crazy as after a violent storm, where trees have bought down powerlines... wandering over to pick up the fallen line to see if it is live.

It is not certain you will be electrocuted if the hair dryer falls in the bath, like in the movies, but that's the movies, fantasy, that's what we do.

The reality is if you are the person who places the light or electrical device into the pool and it either shocks or electrocutes someone...you will be held criminally negligent. Squirting a bit of silicon sealant over the live terminals and thinking it is O.K....doesn't work either. Use only approved underwater lights (eg. Hydroflex Sea Pars or low voltage transformer isolated lamps) and also get advice from the manufacturer on safety precautions, the cost of the hire seems insignificant when you are giving evidence at the inquest.

As an aside I once gave a technical submission (for the defence) in a Court Hearing where a guy had electrocuted himself drilling a hole in the skimmer box of his pool, with his power drill. He was submerged to the waist in the pool-water at the time. The insurance company argued that the guy took no precautions to perform a potentially lethal task, and virtually he committed suicide.

Graham Rutherford
Gaffer Australia



Graham Rutherford wrote:

>...As an aside I once gave a technical submission (for the defence) in a >Court Hearing where a guy had electrocuted himself drilling a hole in >the skimmer box of his pool, with his power drill.

So who won (obviously not the electrician)?

Wade K. Ramsey, DP
Dept. of Cinema & Video Production
Bob Jones University
Greenville, SC 29614



>I believe the reason no one has commented on this post is that it is just >so goddam idiotic. It rates with the morons who get those Darwin >Awards for the most stupid way to kill yourself.

Graham,

You would be surprised how many shoots I attend where they have built underwater set pieces using standard lights underwater. When I first read the post, it was so far off centre that it didn't warrant comment. But in retrospect, it should be stated over and over again. Not only should the equipment be designed for this type of application, it is also wise to source individuals that have worked in a water based environment before.

Common sense rules don't apply and the penalty for assuming is fairly severe.

Vince Pace
PaceHD Productions



>I've put a 1K Molequartz Molepar in swimming pool and turned it on, it >worked just fine.

What about accounts of naked 5K globes lowered into pools then turned on for those *aqua ballet* movies (Ethyl Merman?) shot in the *50s?

<g>

There was a thread here a few years ago... Maybe it's in the
archives?

David Perrault, csc



David Perrault writes;

>What about accounts of naked 5K globes lowered into pools then >turned on for those *aqua ballet* movies (Ethyl Merman?) shot in the >*50s?
>There was a thread here a few years ago...Maybe it's in the archives?


I'm not sure of the archives, but I seem to remember reading about it while going through back issues of AC mag looking for something else. As mentioned by Ed Meyers, lighting with ordinary studio lamps underwater was done extensively for "The Deep". Also, it was Esther Williams, not Ethel Merman, who, btw, is still swimming every day, despite her exposure to electricity under water.

Brian "Were you thinking of mermaids (Merman), David?" Heller
IA 600 DP



Wade K. Ramsey writes :

>The insurance company argued that the guy took no precautions to >perform a potentially lethal task, and virtually he committed suicide.

Hi Wade...... Nup .. No winners


We argued the technical aspects of water/electrical safety and pool deaths due to electrocution.. explaining that there were safety factors that couldn't possibly be understood by the layman.

The Insurance company Lawyer argued, he was taught as a child that the combination of water and electricity could kill you, and this was a generally accepted fact.

He doubted if we could find a member of the Public willing to take an electrical device not designed for immersion in water, apply power to it and jump into a swimming pool. We would need to find someone who had either a complete disregard for living or was a Simpleton.

I only wish I could have produced a couple of the guys who put bare 5K globes in the water.

Still I guess this is why on a film now, I am deluged with safety related paper work, and there is even a Safety Officer to help me cross the street.

Graham Rutherford
Gaffer Australia



Graham Rutherford writes:

>I only wish I could have produced a couple of the guys who put bare 5K >globes in the water.

Too bad you couldn't get in touch with anyone who worked on "The Deep"

The March 1979 issue of American Cinematographer is nearly entirely dedicated to the filming of "The Deep".

In an interview with the DP Christopher Challis, BSC, the interviewer, Michael Samuelson, asks Challis : Can you tell me what sort of lights you've been using underwater?

Challis : That's quite an interesting story, really, because the underwater people, who were originally meant to be absolutely self-supporting (as indeed they were) used sealed beam AC lamps. But these were very small -- only 1,000 watts. I talked to people back home about it and now they are using regular 5 kilowatt lamps. These are ordinary 5-k's, but they've just done away with the switches and sealed the cable ends straight onto the terminals of the lamps which makes the terminals waterproof. Provided the lamps are immersed in the water before they are lighted, they work perfectly well underwater .......

There is an accompanying photograph of crew members lowering a Mole 5,000 watt Senior studio fresnel into the specially constructed tank for "The World's Largest Underwater Set."

Brian Heller
IA 600 DP



Graham Rutherford writes :

>I only wish I could have produced a couple of the guys who put bare 5K >globes in the water.

I worked with a gaffer today who told me how he heated a hot tub with a 10K globe while- folks were in the tub. He also said that on THE ABYSS they used a standard tungsten lighting package in and around the water. ALL due to the magic of DC.

This reminds me of the AC DC war that Edison had with Tesla. Edison took the job of designing the first electric chair for the state of Connecticut and then used it as PR for HIS system, DC. (he used AC to operate the
chair) "See, AC kills!"

I will always use the safest, most reliable equipment available, and defer to the better judgment of specialists (and insurance companies). Location shooting requires that we deal with a mysterious force in an unusual manner.

I'm certainly not advocating DC- just musing on an earlier post about what sort of generators might require grounding and why.

Edwin Myers, Atlanta DP



Edwin Myers wrote :

>This reminds me of the AC DC war that Edison had with Tesla. Edison >took the job of designing the first electric chair for the state of >Connecticut and then used it as PR for HIS system, DC. (he used AC to >operate the chair) "See, AC kills!"

Didn't he try to refer to electrocuting as "Westinghousing?"

Jeff "progress is our most important product my ass" Kreines



>I worked with a gaffer today who told me how he heated a hot tub with a >10K globe while- folks were in the tub. He also said that on THE ABYSS >they used a standard tungsten lighting package in and around the >water.

He ought to stop telling you lies:

http://www.hydroflex.com/site/about/ldareprint.html

Walter Graff
BlueSky, LLC



>He also said that on THE ABYSS they used a standard tungsten lighting >package in and around the water.

To which Walter responded,

> He ought to stop telling you lies :

> http://www.hydroflex.com/site/about/ldareprint.html


Oops, excuse me. I'll see this fellow on Tuesday and I'll ask him to be more specific.

Edwin Myers, Atlanta



Walter Graff writes :

>He ought to stop telling you lies:

>http://www.hydroflex.com/site/about/ldareprint.html


Nice article.

I wonder how the igniter electronics fared in such close proximity to the lamp, and without ventilation. I guess the casing had plenty of water cooling on the outside.

One of my first thoughts on seeing the diagrams was the electrical consequence of explosive lamp failure blowing out both the layers of front glass, but the strict bonding and double safe GFI arrangement is obviously their answer.

Personally I wouldn't have got the lamp manufacturer to do the custom lamp, but would have just tolerated the extra layer of glass and existing connectors purely for the ease of getting replacement lamps.

How do those underwater pluggable mains connectors work??? I'm not sure I'd be comfortable plugging them together or pulling them apart!

Clive Mitchell
http://www.bigclive.com



Clive wrote...

>How do those underwater pluggable mains connectors work? I'm not >sure I'd be comfortable plugging them together or pulling them apart!

Hydroflex pars I have used had a rated underwater plug and receiver, with a locking shroud that relies on a double 'O' ring seal. They come with a tube of Teflon lubricant grease. They can be a bit of a chore but seem safe enough to bet your life on them.

The original post concerned submerging a regular lighting fixture in water ... no mention of any sort of insulation to exposed terminals, switches etc.

Then to 5K globes with the Bi-Post terminals insulated dropped into water .. and despite some reservations (I just bet there were as it even looks dangerous) it was quite safe.

You are literally betting your life that there is no insulation breakdown on the active and a neutral doesn't become detached or open circuited.

I won't even comment on exposed uninsulated A.C. terminals submerged in water.

You wouldn't get away with placing anything in a tank on a film nowadays unless it was approved for submersion.. everything electrical near a tank (video- split etc.) has to be tethered so that if it was accidentally knocked it couldn't possibly fall into the water.

Graham (I try to keep out of the tank)Rutherford
Gaffer Australia



RE : The Deep

These are ordinary 5-k's, but they've just done away with the switches and sealed the cable ends straight onto the terminals of the lamps which makes the terminals waterproof. Provided the lamps are immersed in the water before they are lighted, they work perfectly well underwater.

Are these running off DC then?

Byron Shah
DP LA



Clive wrote...

>How do those underwater pluggable mains connectors work? I'm not >sure I'd be comfortable plugging them together or pulling them apart!

Hydroflex pars I have used had a rated underwater plug and receiver, with a locking shroud that relies on a double 'O' ring seal. They come with a tube of Teflon lubricant grease. They can be a bit of a chore but seem safe enough to bet your life on them.

Are these designed to be mated before submersion though? I'm not sure how they could keep the water out of a connector that was being plugged and unplugged under water as they suggested.

The original post concerned submerging a regular lighting fixture in water ... no mention of any sort of insulation to exposed terminals, switches etc. then to 5K globes with the Bi-Post terminals insulated dropped into water ...and despite some reservations (I just bet there were as it even looks dangerous) it was quite safe. You are literally betting your life that there is no insulation breakdown on the active and a neutral doesn't become detached or open circuited. I won't even comment on exposed uninsulated A.C. terminals submerged in water.

I don't think I'd trust a bit of silicon smeared round the lamp connections either. All it takes is a pinhole for water to get in or a greasy finger print to stop the silicon adhering to the glass to allow water to wick up by capillary action. Come to think of it, the silicon wouldn't reliably stick to some cable insulation's, and as the cable was flexed it could peel away.

Then of course there's the issue of catastrophic globe failure...

But then, in America they do lots of creative things.

Clive Mitchell



Clive Mitchell writes :

> Then of course there's the issue of catastrophic globe failure...

I suspect that at any given moment in marinas and boat yards around the world, thousands of live leads are being dropped into the water by butter fingered boat owners and deck hands, not to mention high voltage under water lines "leaking" voltage. Yet, somehow swimmers survive.

> But then, in America they do lots of creative things.

I'll take that remark in the spirit in which it was offered.

But please, credit where credit is due.

If you would refer back to the quote from AC mag, you would find that the DP on "The Deep" was Christopher Challis, BSC -- as in British Society of Cinematographers, a loyal subject of the Queen as was the rest of the crew. He was interviewed by Michael Samuelson, also of the British Isles. Samuelson's supplied the camera gear as well. The lighting equipment came from Lee Electric.

It was shot in Bermuda, a British territory. So even the electricity was British.

Brian "If electricity comes from electrons... does that mean that morality comes from morons" Heller
IA 600 DP



Brian Heller retorted:

>...It was shot in Bermuda, a British territory. So even the electricity was >British.

Touché!

Wade K. Ramsey, DP
Dept. of Cinema & Video Production
Bob Jones University
Greenville, SC 29614



Clive Mitchell writes :

>Are these designed to be mated before submersion though?
>The ones I have used definitely were... the R.C.D. box stayed on land.. >and you could add lengths of cable, using these waterproof connectors, >to the head unit, which can then be lowered into the water. Then turned >on.....


Brian Heller writes :

>Thousands of live leads are being dropped into the water by butter >fingered boat owners and deck hands. Yet, somehow swimmers >survive.

Unless they become the conduction path...they most probably will.

We tragically had a young electrics die from electrocution while working in a studio here. He went to change the globe in a practical fitting, climbed onto the grid and contacted the live terminal on the lamp base. He couldn't be resuscitated. Changing a light bulb...hundreds of thousands changed every day. It did result, however, in R.C.D's being mandatory for all studios when using supply authority power (mains).

The original post dealt with lights in water.

As the idea of this site is to give advice on aspects of lighting :


A young Film Maker asks : I want to do a underwater sequence. I have the underwater housing, camera, some stock...but I will need to light it as the pool is quite dark. I have four old 5K Moles and there is a large three phase power board, so power isn't a problem.

Do I really need to hire those expensive underwater lights?

I don't want to electrocute anyone esp. me ......

I read on C.M.L. Lighting.. and my understanding is...I can just toss the 5K's lamp heads in the pool as they are, provided I don't turn them on until they are submerged. Is this safe?


Or to be safer, should I remove the globes and attach an extension cord to the terminals, insulate them with some electrical tape and drop them in the pool, As they apparently did this on "The Deep" some 25 years ago.

Graham Rutherford
Gaffer Australia



Graham Rutherford writes :

>We tragically had a young electrics die from electrocution while >working in a studio here. He went to change the globe in a practical >fitting, climbed onto the grid and contacted the live terminal on the lamp >base. He couldn't be resuscitated.

BH : That is indeed tragic. I'm very sorry to hear it.

>Changing a light bulb...hundreds of thousands changed every day

>It did result, however, in R.C.D's being mandatory for all studios when >using supply authority power (mains).

BH : That is a very good idea. We have been pushing for that in the US for some time. Since nearly all electrical devices in the US run on 110, the likelihood of similar incident happening here is not eliminated, but considerably diminished. However, I'm not entirely sure what your point is. That fixtures should be turned off or disconnected when replacing globes? That electricity can be dangerous, even lethal? You'll get no disagreement from me on those points.

>GR : The original post dealt with lights in water.

BH : That's my understanding as well.

>GR : As the idea of this site is to give advice on aspects of lighting:

BH : I respectfully disagree with your interpretation. I see the purpose of CML as somewhat broader than simply advice.

To quote from the CML site :

"Our aim is to promote the free exchange of ideas among fellow professionals working in Cinematography: the cinematographer, his or her camera crew, cinematography manufacturer's, rental house's and other related businesses."

Graham Rutherford further writes :

> A young Film Maker asks...
>I read on C.M.L. Lighting...and my understanding is...I can just toss the >5K's lamp heads in the pool as they are, provided I don't turn them on >until they are submerged. Is this safe?
> Or to be safer, should I remove the globes and attach an extension >cord to the terminals, insulate them with some electrical tape and drop >them in the pool, As they apparently did this on "The Deep" some 25 >years ago.


BH : This discussion about putting film lights in the water started with a discussion of whether or not generators should be grounded. There still seems to be no consensus on that subject, so it's not unreasonable... don’t expect that any agreement will be reached about putting lights in water. It then devolved into a discussion of electricity and water which started with something like :

BH : It's impossible to put regular film lights in water. Then, to it's impossible to put regular film lights in water without their shorting out. Then, to it's impossible to put regular film lights in water without risking electrocuting everyone in the water. Then, to the young film maker scenario.

BH : People brought up cases where film lights have been safely placed in water, and mentioned "The Deep" as an example. Curious about this discussion, I researched the article in AC on "The Deep" and quoted from it.

BH : If you are now suggesting in your zeal for safety that we should not talk about the techniques used to make this film -- as you now seem to be -- or that discussing it is somehow irresponsible because of what you imagine someone might or might not do in the future, I think you are completely off base and labouring under a misconception as to the meaning of "the free exchange of ideas among professionals".

For instance, if we were to talk about the techniques used in the filming of "Ben Hur" and some kids decide to have a chariot race, are we responsible for any resulting mishaps.

Brian Heller
IA 600 DP



Brian Heller writes :

>For instance, if we were to talk about the techniques used in the filming >of "Ben Hur" and some kids decide to have a chariot race, are we >responsible for any resulting mishaps.

Now that's stretching it a wee bit. Although I guess that Jackass has probably spawned a load of copycat stunts with unpleasant results.

On the other hand, we're talking about dropping ordinary lights in water here! This is akin to lighting a model in a bathtub by dropping a redhead in. (Oh dear, now I've made it sound like a lesbian orgy.)

As far as the yachtsman dropping a live lead in water goes, if water entered the live connection first, then there would be a strong voltage gradient to the nearest ground planes. Anyone swimming in the direct vicinity of the lead could find themselves with a significant voltage across their body.

Clive Mitchell



Clive Mitchell writes :

>Now that's stretching it a wee bit. Although I guess that Jackass has >probably spawned a load of copycat stunts with unpleasant results.

In America, there is a reality TV series based on lamebrained stunts.

I used "Ben Hur" as an extreme example (figuring not too many people had access to chariots these days) only to make the point that mere discussion is a far cry from encouragement or instigation. I should have used "The Great Voltini" instead. By the way, don't try this at home, kids...

>On the other hand, we're talking about dropping ordinary lights in water >here! This is akin to lighting a model in a bathtub by dropping a >redhead in.

Yet, they did it for many days on end with apparently no ill effect.

>(Oh dear, now I've made it sound like a lesbian orgy.)

That movies on a different website. Cf: Jeff Kreines

>As far as the yachtsman dropping a live lead in water goes, if water >entered the live connection first, then there would be a strong voltage >gradient to the nearest ground planes.

I'm not questioning the theory, or the possibility. However, it would seem that the reality doesn't conform to the theory at least in apex of "The Bermuda Triangle."

Brian "Where's Jack Palance when you really need him." Heller
IA 600 DP



There is a good write-up on underwater lighting in the "Set Lighting Technicians Handbook" - Harry Box.

My understanding is the only way it comes even close to being "safe" is with DC power.

Dave Winters
DP - L.A.



Brian Heller wrote :

BH : This discussion about putting film lights in the water started with a discussion of whether or not generators should be grounded. There still seems to be no consensus on that subject.

GR :I don’t expect there will be...The regulating authorities (in most cases) don’t have a code of practice for a mobile generator supply unless it is to be connected as a stand-by power source in case of failure of the main electricity supply grid....The no earth stake argument requires an understanding of what a floating power supply is. That you are creating another potential, active to ground (earth) unnecessarily, by earthing the generator.

I think the gist of the drive an earth stake argument is that the generator may produce lethal voltages to (earth) ground unless it is earthed via an earth stake, or equipment may have a potential to earth (ground), or it may even be struck by lightning , I think someone suggested..

The new inverter type portable generators which require a load to produce voltage will cause further head scratching

BH : People brought up cases where film lights have been safely placed in water, and mentioned "The Deep" as an example
However, I'm not entirely sure what your point is

GR :My point was simply No one was saying Exercise Caution just that it was O.K. to do it. I believe so many of these things were done in the past in the Film Industry not because people fully understood the risks or had carried out safety tests but just they had seen someone else do it.

BH : If you are now suggesting in your zeal for safety that we should not talk about the techniques used to make this film -- as you now seem to be --

GR :I wasn’t suggesting that for a moment but I believe there is a responsibility to point out potential dangers.

For example I tell Film Students not to point open eye lamps, like the good old Red Head at people, unless the lamps are fitted with wire scatter guards and if possible to use a gel or diffusion as well.

These lamps have been used for years and a globe explosion may be fairly rare, but you don’t want to be the one picking the molten quartz glass out of someone’s face or commiserating about the burn hole in the expensive carpet.

I well remember Arc Scissors used to produce a lightning effect. They were usually constructed from Brute arc carbons, attached to two pieces of wood (but I have seen professionally made ones) and powered from a 1000 amp D.C. generator. A person wearing a welding mask (or if they were really macho, just looked away) would make the carbons contact producing a blinding lightning type flash it worked but I wouldn’t recommend it, unless the person involved was competent, understood the risks and took some safety precautions, but I would be the last one to say you cant do that..

But back to lights in water... I know a lot of people believe D.C. is safer than A.C. Certainly just a film of oil on your fingers can be enough to insulate you.

I wonder if anyone has tossed a D.C. brute arc into a tank of water, you could actually strike it and have it burning first .

I AM JOKING!!!!!!!!!!!!

Graham Rutherford
Gaffer Australia


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