Electric Arc Lighting Effect

20th May 2007

Hi all,

I have a scene in an upcoming film with arcing electric bolts coming out of an alien. The arcs will be CGI but I need a light source that will mimic them and to light up the background and other characters. I was thinking about using an arc welder and was wondering if anyone has tried this and if so how they did it. Or any other ideas.
Thanks

James LeGoy
DP
LA

Even a large arc welder won't provide very much light unless your using a set of large gouging rods. Brushing a couple carbon arc rods together is really the way to go but neither are very safe in the film environment. Welding arc light produces a significant amount of UV light as well as sulphur dioxide and other toxic gases. Not exactly
crew friendly.

A couple small lighting strikes or even a small HMI with a set of shutters will give very similar effects and are osha friendly.

Make sure you provide the production with the proper MSDS literature if your planning to use a welding arc.

Erik Messerschmidt
CLT, LA

Hi James

Have a look at the "Martin Atomic 3000" DMX it can be triggered manually and has a blinder effect.. that is it can be held on for whatever duration you want for the flash. 5600 degrees K, I use them often on interior sets for lightning effects.

You can also slave multiple units.

Concert lighting hire companies carry them and they are cheap to hire.
You can look up www.Martin.com for more info.

Graham Rutherford
Gaffer
Australia

What about a lightning strike :

http://www.lightningstrikes.com/

I’ve used them for like situations.

Jared Hoy
Los Angeles, CA, USA
Gaffer || BBE

Graham Rutherford writes :

>>"it can be triggered manually and has a blinder effect.. that is it can be >>held on for whatever duration you want for the flash"

The web site is a little unclear how it achieves the blinder effect, have you had any issues with flicker or strobing when in blinder mode?

Thanks

Jake Capistron
LA

James LeGoy writes :

>>I have a scene in an upcoming film with arcing electric bolts coming >>out of an alien.

I did this for a TV production using custom LED panels and a dedicated controller.

One workable option using standard lighting gear might be to use a lighting desk running a programmed sequence on something like a High End Data Flash. This would be bright, but they have a limit on how long they can run when used in "full on" mode.

I take it that one of the smaller units from the Lightning Strikes range has been considered?

If you want to experiment with an LED based lighting panel, then you could build the little RGB controller project on my website. The second program is white lightning.

Clive Mitchell
http://www.bigclive.com

Hi Jake,

I have only used the Atomic 3000 for effects, lightning flashes etc. I haven't had any problems with flickering or strobing, but I am only holding the flash duration on for the maximum of a couple of seconds. I haven’t tried using them like a poor man's soft sun, (i.e.) holding the blinder effect on indefinitely.

In the past I had tried strobes, but the flash time is extremely short in the thousandths of a second and the old adage, 'If you saw the flash in the view finder you probably didn't get it on the film.'

I loved the atomics because they allow you to randomise the length of the flashes, some short, some long, slow fast, either violent or sedate, making the effect more believable. Also you are sure the camera (i.e.) the film, has seen the flashes as the flash duration is so long.

I often don't have the budget to have the lightning strikes sitting around on set for a week or so. The light output from the 3000's is quite surprising but they are not "lightning strikes" able to light large areas of exterior, however in sets I have used the 3000's with great effect.

I am not a salesman for 'Martin' and I am sure there are other lamps that will do the same job as the Atomics, there may even be bigger and better ones now, but I had been looking for something that would give a believable lightning effect when I didn't have the 'lightning strikes'. Plus the 3000's were readily available here and are cheap to rent.

Graham Rutherford
Gaffer
Australia

Hi Everyone

Thank you for your responses.

Graham, your description of the Martin Atomic 3000 makes me believe it is just the ticket, I am going to look at it tomorrow to see if it works for me. Eric, good words of warning.

Thanks again.

James LeGoy
DP, LA

>>I haven't had any problems with flickering or strobing, but I am only >>holding the flash duration on for the maximum of a couple of seconds. >>I haven’t tried using them like a poor man's soft sun, (i.e.) holding the >>blinder effect on indefinitely.

The Atomics will overheat like a lightning strike if you hold down the blinder for more then a few seconds, they probably refresh at a standard 60hz so they shouldn't flicker at 24 frames but they aren't designed for continuous flicker free lighting. If you like the quality of the atomic but need them to stay on a 4k goya head will give you those nice sharp shadows.

Erik Messerschmidt
CLT, LA