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shooting near water


Daniel Madsen

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Lets say I want to place lights near (read-"near") the surface of a swimming pool with people in the water. What procautions do you take? Can you put individual GFCIs on every light? And just for my own education, is DC used exclusively to shoot underwater or is there an AC system? I read that using ground fault protection is best on small light sources, certainly not an entire power plant.

 

 

Unrelated question- where would I find underwater speakers to be used by an artist to lip sync to while....you guessed it... underwater (and not being fried)?

 

Peace be with you.

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I would very strongly suggest getting an experienced electrician for your shoot because you are talking about one of the ultimate potential danger situations that exist.

 

If I were in that situation, I would probably make sure the length of the power cord, the stand, and the light could never reach the pool intact. The idea being if a light fell over it would automatically have to disconnect from the power source or be tugged away from the pool.

 

Remember in Body Double when the murderer with huge drill in hand goes to attack a women and the power cord unplugs before he can reach her. I'm sure there are other issues to consider as well.

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because you are talking about one of the ultimate potential danger situations that exist.

 

no?

----

 

 

I'm suprised people have nothing to contribute in the area of underwater cinematography. 70% of the Earth is covered by water not to mention all those damn pools.

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Lets say I want to place lights near (read-"near") the surface of a swimming pool with people in the water. What procautions do you take? Can you put individual GFCIs on every light? And just for my own education, is DC used exclusively to shoot underwater or is there an AC system? I read that using ground fault protection is best on small light sources, certainly not an entire power plant.

 

Unrelated question- where would I find underwater speakers to be used by an artist to lip sync to while....you guessed it... underwater (and not being fried)?

 

Peace be with you.

 

NEC requirements are that all outlets in pool areas be GFCI enabled. So you can first look for local outets around the pool and use those. Test the GFCI curcuit switch to make sure fixture is workign properly. If you need more power, you can purchase a portable inline GFCI curcit breakers at stores such as Home Depot. Since you are not familar with this situation do make sure all power goes to a GFCI curcuit.

 

As for lights. Make sure they are far enough away from pool so as not to fall in (including the total lengh of stand once it is raised. Sand bag all sands well. Also make sure all plugs have three prongs. Do not use plugs where the ground pin is missing. Do not use three to two prong convertors. Be safe with cables making sure they are taped down and covered so no one trips. Cable runs should always be heading away

from pool and not around it like a lasso. Get yourself one of those little three prong curcuit testers that will tell you if the wiring in the house is correct. Test each outlet you plan to use. If it shows a ground fault DO NOT USE THE OUTLET. Lighitng around pools need not be scarey if you simply follow common sense.

 

As for underwater lights. No many of todays productions use AC fixtures.

 

As for underwater speakers a search on the web wil bring up a hundred companies that make them.

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What does GFCI stand for?

 

In the states GFCI stand for ground fault circuit interrupter. I believe in Europe they are called RCB or RCCB Residual Current Circuit Breaker. Point is any damp area where you use electricity should have them installed between fixture and source. They detect the smallest leak in voltage and trip an internal breaker protecting you more than a regular circuit breaker can.

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My experience around water has been limited to some underwater/aqua PAR's rented for swimming pool scenes. Otherwise, it's mainly been about safety rigs for lights on dry ground that could potentially fall into a pool, and safety rules around the pool (like no one unnecessary in the water during a lighting set-up, etc.) Yes, if there is any real possibility of a light going into the water, then GFCI's would be used.

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My experience around water has been limited to some underwater/aqua PAR's rented for swimming pool scenes. Otherwise, it's mainly been about safety rigs for lights on dry ground that could potentially fall into a pool, and safety rules around the pool (like no one unnecessary in the water during a lighting set-up, etc.) Yes, if there is any real possibility of a light going into the water, then GFCI's would be used.

 

Isn't DC used for underwater stuff? I've stood in pools full of 10k's, unnerving but never felt a thing :)

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Isn't DC used for underwater stuff? I've stood in pools full of 10k's, unnerving but never felt a thing :)

 

I did a commercial in swimming pool a few years ago. The Gaffer wouldn't let any AC power within 30' of the water. All the lamps were running on DC.

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I did a commercial in swimming pool a few years ago. The Gaffer wouldn't let any AC power within 30' of the water. All the lamps were running on DC.

I'm curious, what voltage DC? I wouldn't particularly want to be in a pool with 120 volts DC around either. DC is kinder about killing you - but not enough for me to bet my life on.

 

See http://www.vias.org/feee/safety_03.html

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AC voltage is more dangerious because it changes polarity and messes with your heart. That and also the current in a shorted AC curcuit will find the path of least resistance to the ground, be it a human or pool of water.

 

The only way to get zapped with DC is if you are touching the + and - terminals at the same time. Keep in mind if an open DC curcuit is underwater it will still create a deadly electric field around the open curcuit.

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I think a bunch of us covered this topic a year or more ago. It was an informative thread with lots of tricks of the trade. Try a search. I can't recall how the thread started so I don't know what to tell you to search under.

 

Many people here may not provide answers since there is some degree of liability on this topic. It's not that they don't care. It's just a hairy topic.

 

Good luck.

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I did a show about 3 months ago around a pool and water fountain. We had 4 kino's in the fountain, 2 2k's in the pool, a 4k hmi above and a bunch of smaller stuff. I had never shot around water and didn't want to be the guy responsible for seriously injuring or killing someone. We contacted Bender and hydroflex. These guys are great and willing to help out, give demo's and answer any general question.

 

www.hydroflex.com Hydroflex rents lights and housings designed specifically for underwater lighting.

www.bender.org Bender can provide all of you gfci's.

 

We had a 1000 amp AC plant on set and everything went smoothly.

We also had a 25k softsun on the other side of the building mounted on a scissor lift.

 

Here is our power distribution diagram for the night.

Hope it makes sense.

 

Bradley W. Stonesifer

Director of Photography

post-8812-1170320937.jpg

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  • 1 month later...

Call Hydroflex, I get everything through them. They have GFCI's ranging from 300amps, to 20amps. My above-water gaffer puts 300amp and 100amp GFCIs straight out of our genie. They also offer 20amp GFCI's the just go in-line with your edison-power cable.

 

I've been in a tank with over 400amps of power flowing into the water to our hydropars/hydroflows/etc. We had a 4k leak power into the pool, tripped the GFCI, and all we felt was a small pinch.

 

I just did the unerwater unit for THE TRIBE (for LionsGate) and they didn't want to get the GFCI's, but after some convincing they did (we had 2x 10ks and a couple 5ks 10' from the water).

 

And the New KillSwitch EnGage music video, 4x 18k's litteraly 2' from the pool-edge (as far as possible at that location) but we had the GFCI's on, and they were harnessed, and all connections were lifted off the deck with full-apples to keep any connections from getting wet.

 

Safety Diver, If you are in water, I would strongly suggest having one. I do not know what the SAG rules are, but I have almost had 2 AC's die underwater, I saved one (dragged her to the surface) and our safety diver saved the other. Plus, as an underwater DP, with a great crew, that spends tons of time underwater, I love to have a great safety diver, becuase they watch your back, you can't know whats going on above-water when you are working underwater. (A remote-aqua crane almost ripped my BCD off because the grips were not paying attention and trying to move the camera into position.)

 

Underwater speakers. Again go to Hydroflex.com and there is so much info there...they have almost all the gear you could need.

 

Ian S. Takahashi

Underwater Cinematographer

post-13864-1174013093.jpgpost-13864-1174013101.jpgpost-13864-1174013486.jpg

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DC is definately safer for water work.

 

"AC sticks and DC kicks" as the expression goes.

 

The Bender GFCI's are terrific products for AC and DC protection though personally I have never used the DC versions. Just the AC. They really work with the slightest perception of voltage leak.

http://lightingballoons.com/gfci.htm

 

Just because no one mentioned it yet: don't forget that tungsten can be used on AC or DC but HMI, Kinos, video and sound equipment can only be used with AC (unless other precautions are made). For those who do not know.

 

Best

 

Tim

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