Tips needed for practical lightning

I'm trying to come up with an on set lightning effect. Not a digital effect. Like in horror films, when the lightning flashes on the actor's faces. That sort of thing. I'm pretty sure in the old movies it was done with a spot like and some sort of shutter system. If anyone has a link to an article on how it was done, or any ideas how to recreate the effect on a set. My budget is limited, but not non-existent. So I can spend a little on lights and equipment... but i can't splurge on a $1000 light set up. Any help is appreciated.

The trick to lightning is that its very directional, so you only need one really bright light. But it has to be bright enough to overpower all the other lights providing the general illumination of the scene. Its important that the light be from one direction, and that it create hard shadows when it is present. Then you just need a bit of black card to cover the light, and somebody to move the card back and forth to create the flashing.

The closer you can get the light to your subject, the more easily it can overpower whatever other lights you have going. Inverse square law and all that. And since the light is meant to be harsh anyway, having it as close as you can get without the light being in frame, is probably your best bet.

The trick to lightning is that its very directional, so you only need one really bright light. But it has to be bright enough to overpower all the other lights providing the general illumination of the scene. Its important that the light be from one direction, and that it create hard shadows when it is present. Then you just need a bit of black card to cover the light, and somebody to move the card back and forth to create the flashing.

The closer you can get the light to your subject, the more easily it can overpower whatever other lights you have going. Inverse square law and all that. And since the light is meant to be harsh anyway, having it as close as you can get without the light being in frame, is probably your best bet.

any particular light set up you would recommend?

Well, start by lighting the scene as you would for the non-lightning bits of footage, as that is what you will want to be exposed for, then add one additional light, coming from the side where the lightning would naturally be. Use your brightest light there, if you have lights of different power ratings, and get it as close to the subject(s) as possible. If you have the resources, you might also consider placing two lights side by side, as close together as you can, to intensify the lightning. Then as you wave the card in front of them, sometimes only one light will show, sometimes both, and it might give a bit more life and movement to the effect.

I'm not really a DP, but that's how I would approach it.

i thought about using a bright strobe, but i think it would be too regular. I think it would look like a strobe and not lightning

I agree.

Just watched the commentary track to Mad Max, there is a scene where Mel Gibson sits up in bed from a nightmare and there is a red slash of light right across his eyes. In the commentary they said it was done by cutting a slash in a cardboard shoe box and putting it over the light. Not the effect I am looking for but I thought it was interesting just how low tech it was done. Might see if I can come up with something equally low tech for my lightning flashes.

You mean like a bit of black card being waved in front of a bright light?

You mean like a bit of black card being waved in front of a bright light?

lol well i was thinking of trying to set up something slightly more high tech than that. Kinda thinking of a box with a shutter system. I'm sure I can find some sort of louvered shutters at home depot or something.

hmmmm something like this maybe

http://www.amazon.co...uvered shutters

Well I will just say one thing, I used these photography flash lights, which you can flash on and off ins split second, the bad thing is that when I was setting up these lights to use (I was told they were for video, and would be continuously on, and not just flash) I noticed they weren't coming on, so I went round the front to see if the light bulb was in, at that point my friend pressed something on the light, which caused an intensely bright light that flashed, from point blank range, into my face!
After that I couldn't really see for about 5 mins.

So yeah, you can use photography flash lights, I don't know if you have already mentioned that before in this thread as I haven't had enough time to read it.