Jump to content


Photo

Lightning


  • Please log in to reply
17 replies to this topic

#1 Richard Boddington

Richard Boddington
  • Sustaining Members
  • 5482 posts
  • Director

Posted 11 April 2006 - 09:19 PM

Hi,

Any one here ever created lightning on a budget?

I'm sure there's a big fancy expensive system for creating lightning flashes on a set to simulate a thunder storm outside. But I don't have budget for that.

Any cheap ways to do it?

Lights that can plug into regular AC and flash via a capacitor?

Any ideas out there?

Thanks
R,
  • 0

#2 James Steven Beverly

James Steven Beverly
  • Basic Members
  • PipPipPipPip
  • 4199 posts
  • Director
  • El Paso, Texas

Posted 11 April 2006 - 10:35 PM

Use a momentary switch on a set of halogens.
  • 0

#3 Dan Goulder

Dan Goulder
  • Sustaining Members
  • 1259 posts
  • Cinematographer

Posted 11 April 2006 - 10:46 PM

Use a momentary switch on a set of halogens.

...and if you see any real lightning, it's time to bolt.
  • 0

#4 Michael Nash

Michael Nash
  • Sustaining Members
  • 3330 posts
  • Cinematographer
  • Pasadena, CA

Posted 11 April 2006 - 11:04 PM

Shutters on a 10K -- that's how they used to do it.

The problem with momentarily powering tungsten lights is that the filaments take a little while to die down. You get this "decay" that doesn't look convincing.

You can augment or even create the illusion of a lightning flash in post sometimes, if it's brief. Along with sound effects, it's enough to fool some of the people some of the time...
  • 0

#5 David Mullen ASC

David Mullen ASC
  • Sustaining Members
  • 19769 posts
  • Cinematographer
  • Los Angeles

Posted 11 April 2006 - 11:10 PM

Yes, metal shutters (similar to venetian blinds) on an HMI is the cheapest method, assuming you can afford the HMI.

Ordinary strobes / flashes tend to fire too quickly and regularly for lightning.
  • 0

#6 Chris Pritzlaff

Chris Pritzlaff
  • Basic Members
  • PipPipPip
  • 187 posts
  • Gaffer
  • Los Angeles

Posted 12 April 2006 - 12:29 AM

Try a DataFlash strobe system. I used them on a shoot and they worked out quite well. I'm not sure how expensive they are to rent though.
  • 0

#7 Scott Fritzshall

Scott Fritzshall
  • Basic Members
  • PipPipPipPip
  • 584 posts
  • Other
  • Los Angeles

Posted 12 April 2006 - 12:31 AM

Shutters on a 10K -- that's how they used to do it.

Coincidentally, I used precisely this method just a few hours ago. It looked surpisingly good- not perfect, but certainly acceptable.
  • 0

#8 Richard Boddington

Richard Boddington
  • Sustaining Members
  • 5482 posts
  • Director

Posted 12 April 2006 - 10:16 AM

Thanks for the suggestions, but when I said "budget" I mean I won't have a 10K or the generator to power it.

I've been fooling with flashes on cameras, it looks like lightning but it's so quick, maybe 1-2 frames worth of light. Provided the shutter is even open when it fires and it gets captured on film.

Some form of strobe may be my only option.

I have 650W film lights that plug into house current, maybe some quick opening blinds on those will work?

But 650W is a long way from 10K isn't it?

Thanks
R,
  • 0

#9 Phil Rhodes

Phil Rhodes
  • Sustaining Members
  • 11943 posts
  • Other

Posted 12 April 2006 - 01:45 PM

Hi,

Car battery, or welding set.

Two carbon rods.

Phil
  • 0

#10 Emre Safak

Emre Safak

    New

  • Basic Members
  • Pip
  • 4 posts
  • Student

Posted 12 April 2006 - 02:08 PM

I don't know if it is an option, but if it comes to the worst you could use your 650W and amplify the effect in post-production.
  • 0

#11 Richard Boddington

Richard Boddington
  • Sustaining Members
  • 5482 posts
  • Director

Posted 12 April 2006 - 05:31 PM

What do I do with the car battery Phil?

Just touch pos and neg together via the carbon rods?

R,
  • 0

#12 Luke Prendergast

Luke Prendergast
  • Sustaining Members
  • 491 posts
  • Cinematographer
  • Victoria Australia

Posted 12 April 2006 - 05:38 PM

Just touch pos and neg together via the carbon rods?


...and you have a Carbon Arc lamp. Old school. Very bright. They smoke a bit though.
  • 0

#13 Richard Boddington

Richard Boddington
  • Sustaining Members
  • 5482 posts
  • Director

Posted 12 April 2006 - 09:41 PM

Seriously two carbon rods from a car battery?

Has any one actually done lightning this way?

You put the rods on wires I assume and then briefly touch them?

Thanks
R,
  • 0

#14 Hal Smith

Hal Smith
  • Sustaining Members
  • 2280 posts
  • Cinematographer
  • OKC area

Posted 12 April 2006 - 10:43 PM

Wear UV proof sunglasses, electrician's gloves, and a face shield if you're going to try making Lightning with old carbon rods. There's an old SMPTE paper on high performance carbon arc lamps at:

http://www.mole.com/...1947-07p37.html

The big boys used DC voltages in the 70 volt range and currents around 200 amps - not easy to figure out how to generate. Old Strong SuperTrooper Arc followspots have gotten pretty cheap, you could probably make a pretty effective lightning generator out of one.
  • 0

#15 James Steven Beverly

James Steven Beverly
  • Basic Members
  • PipPipPipPip
  • 4199 posts
  • Director
  • El Paso, Texas

Posted 13 April 2006 - 02:27 AM

An arc welder would probably do it if yyou have one available, but you may need to see if you'll need 220vt to power it. Not to beat a dead horse, if you combined 4 to 6 halogens or strong outdoor spot or flood screw in type bulbs w/ ceramic fixtures screwed to a piece of plywood w/ a set of wooden or metal shutters over the front and box sides to control your light bleed you would eliminate the "decay" Michael Nash mentioned, altough, I always tought that drop off made the effect look more like natural lightning as natural lightning seens to often taper off. This method would allow you to use standard 115 volt household current and it should be very affordable. This is stuff you could probably scrounge or buy for a few bucks.

My first set of stage lights were made out of coffee cans painted black w/ screw in spot bulbs and ceramic fixtures and scrounged electrical cords. I also had a dimmer board built using a few household dimmer switches. I made up about 40 of these homemade par cans and they worked terrifically. I even built gel frames for them out of 20 gauge galvanized sheet metal and used 1/8th in thick 1 in metal strapping to fabricate yokes and cast pipe hangers to hang them. I still use them on occation when I need a lot of fill light although it's rare as I have more proffesional equipment now.
  • 0

#16 Adam Frisch FSF

Adam Frisch FSF
  • Sustaining Members
  • 2009 posts
  • Cinematographer
  • Los Angeles, USA

Posted 13 April 2006 - 03:03 AM

Another trick is to overexpose your stock say 3 stops (and live with the extra grain in whites), then pull it back down in post to normal and just edit in the overexposed frames for the lightning effect.
  • 0

#17 Phil Rhodes

Phil Rhodes
  • Sustaining Members
  • 11943 posts
  • Other

Posted 13 April 2006 - 05:25 AM

Hi,

> Seriously two carbon rods from a car battery?

Yes.

> Has any one actually done lightning this way?

Yes. Well actually I used an old mains transformer which had a valve heater winding. If you short either of these out for too long they will overheat, catch fire, vent boiling acid, set off the smoke alarms, etc. Be judicious.

> You put the rods on wires I assume and then briefly touch them?

Yes. Big, big cabling - welding cable. You won't actually be able to hold them together for long as they will "chatter" like a bad welder, but have an emergency disconnect in case they get welded. Obviously, this is relatively unsafe, a fairly big fire risk and will require complete protective equipment. It also produces copious quantities of UVA and UVB, although briefly, and a fair amount of CO in the form of a cloud of noxious smoke - I'd hesitate to do it indoors, unless a particularly big studio with the doors open. I was lucky enough to get some projector carbons which have a copper sheath, making it easy to connect them up, but then you also have globs of molten copper (green sparks) flying everywhere.

Tons of fun, but not tremendously safe. You get exactly the same effect you got in old films where the'd just bang brute arc carbons together.

Phil
  • 0

#18 Jordan Roettele

Jordan Roettele

    New

  • Basic Members
  • Pip
  • 7 posts
  • Student
  • BK, NYC

Posted 16 April 2006 - 11:21 AM

Hi,

Any one here ever created lightning on a budget?

I'm sure there's a big fancy expensive system for creating lightning flashes on a set to simulate a thunder storm outside. But I don't have budget for that.

Any cheap ways to do it?

Lights that can plug into regular AC and flash via a capacitor?

Any ideas out there?

Thanks
R,


What about a strobe light?
I'm sure you can control the time inbetween the light flashes.
  • 0


The Slider

Tai Audio

CineLab

Rig Wheels Passport

Broadcast Solutions Inc

Paralinx LLC

Gamma Ray Digital Inc

FJS International, LLC

Media Blackout - Custom Cables and AKS

rebotnix Technologies

Abel Cine

CineTape

Metropolis Post

Aerial Filmworks

Wooden Camera

Visual Products

Technodolly

Ritter Battery

Glidecam

Opal

Willys Widgets

Visual Products

Willys Widgets

Opal

Gamma Ray Digital Inc

CineTape

Rig Wheels Passport

Wooden Camera

rebotnix Technologies

Paralinx LLC

Broadcast Solutions Inc

FJS International, LLC

Technodolly

Glidecam

Tai Audio

CineLab

Aerial Filmworks

The Slider

Metropolis Post

Ritter Battery

Media Blackout - Custom Cables and AKS

Abel Cine