Sunlight on a Train

[SeeKapRun]

So I'm working on a show where the final scene takes place on a train, and the set is pretty minimal, so we're trying really hard to sell it with light and sound. It's supposed to be early morning, with a sun low in the sky, and I want to create the effect of randomly flickering sunlight, as if the sun periodically passes behind a cluster of branches.

I thought about building some sort of rotator to place in front of a distant point source, but the limitations of the stage mean that I couldn't get a side light far enough away to avoid seeing the shadow of the rotator moving across the actors. Also, having essentially no wings to speak of, it would be hard to hide.

Alternatively, I'm wondering if there's some type of dimmer that would cause "random," periodic flashes, which would allow me to place the fixture relatively close to the actors, and still achieve that look. Furthermore, even if there were a dimmer that could do this, I'd still be nervous that the cooldown time of any tungsten unit I use would make the flashes imperceptible. Is there an LED unit that's capable of this? Or something else entirely?

Thanks for any guidance you could provide!

 

[JD]

How about using a moving head and set up a shutter program?

 

[SeeKapRun]

As an edit to my original post:

Despite my best efforts, I can't seem to find any clips from any films that incorporate the look I'm going for. Plenty of train scenes, but they all seem to have static, constant light. Maybe I'm forgetting an obvious one.

 

[SeeKapRun]

How about using a moving head and set up a shutter program?

Can you elaborate on that? I'm not sure what a shutter program is. (mostly self-taught Lighting Designer in training)

 

[JD]

Well, by using a moving head (although technically not moving), depending on the model, you should be able to get a good color mix as well as a point source. By setting up a "chase" set of cues with different shutter settings you should be able to get the look of passing objects interfering with the source like trees would. In addition, depending on what gobos are installed in it, you may be able to engage/disengage one or more for more of a flicker effect.

 

[Les]

Sounds like a good task for the Gam Film/FX.

 

[zmb]

I think you would be fine with the cool down time of a tungsten source, it will help it look more natural and not too artificial like the instant on/off time that an LED source would have. If you have light board with any sort of programming ability, even an effects engine on a basic 2-scene board, you could make a sequence to pulsate the channels used in the scene.

 

[JChenault]

IMHO the issue hereis that you want a linear motion, not circular.

The gam FX loop is the least expensive way I can see to do this. Combing this with an effect to bring the dimmer uo and down might work well..

I have seen this done well using some kind of ( extremely bright) video projector.

 

[Mandolomo]

I believe a lobsterscope may be just the thing for you in this application. Look it up!

 

[SeeKapRun]

I believe a lobsterscope may be just the thing for you in this application. Look it up!

This is intriguing. I wish there were some videos showing it in action. Alas, YouTube, you've failed me once again!

The problem with this is that it would complicate the connective tissue, the times during which the light should remain constant. I could add a second fixture adjacent to it, and just alternate between the two, I suppose, so long as it doesn't look too obvious.

The issue with programming something is that I've got basically a day and a half (and a couple extra pairs of hands) to hang the entire plot, and we're gonna be coming in just under the wire (pun intended) as it is. Honestly, I could probably just do it manually, if it came right down to it. The scene is short, so if I'm desperately low on time, I could just cheat it.

From my experience with the Gam FX, it's not exactly the look I want, I think, though I haven't tried using it in combination with an effect, as JChenault recommended.

I might look into the projector thing, and probably price check a moving head as well, though that'll demand a decent amount of programming.

This is really great, everyone, thank you all for these ideas. There is much research to be done!

 

[David Ashton]

my suggestion would be to rig 3 lights and run them on a random chase, however don't have them flashing on/off just vary them from full to half to make them more subtle and realistic. You might also look at putting 3 different amber gels in them.

 

[meatpopsicle]

This is intriguing. I wish there were some videos showing it in action. Alas, YouTube, you've failed me once again!

The problem with this is that it would complicate the connective tissue, the times during which the light should remain constant. I could add a second fixture adjacent to it, and just alternate between the two, I suppose, so long as it doesn't look too obvious.

The issue with programming something is that I've got basically a day and a half (and a couple extra pairs of hands) to hang the entire plot, and we're gonna be coming in just under the wire (pun intended) as it is. Honestly, I could probably just do it manually, if it came right down to it. The scene is short, so if I'm desperately low on time, I could just cheat it.

From my experience with the Gam FX, it's not exactly the look I want, I think, though I haven't tried using it in combination with an effect, as JChenault recommended.

I might look into the projector thing, and probably price check a moving head as well, though that'll demand a decent amount of programming.

What you are talking about is moving shadows across your sunlight playing through either real or imaginary train windows. We do this a lot in the film business and there are a few ways we can achieve this.

The 1st is just moving shadows, set up a big source and move tree branches, by hand, through the throw of the light. Usually we are mimicking the light playing through a car's windows as someone "drives" (Poor Man's Process). Depending on your venue this might be achievable off stage.

The 2nd is projecting a gobo onto the scene and either rotating the gobo, or the head, to achieve the movement of the shadows. Using a moving head with a rotating gobo and shutters can make this quite believable. I've had success with a black and white image of the earth rotating through the light and shuttering off half of the image so that the image is only moving one way. The dark sea and light continents become an apt break up - and Asia becomes a fairly constant light as it goes by. By putting the rotational speed on a playback fader you can vary the speed of the rotation from zero to whatever. You then rotate the gobo whenever you want a shadow to go by and stop it over Asia to have your constant light. I've also programmed a cue sequence to rotate the gobo at the correct speed and stop at the right place and put that on a playback. Hit the button and the gobo rotates and then re-sets.

The 3rd way involves setting up the train lights as a multi-unit chase. Hang, for instance, 10 parcans in a row. Write a chase that sets all the cans at 80% and moves the OFF state along the line of cans. This is usually a standard chase set to [invert]. With the chase set as a single shot and put onto a effect playback you can hit the go on the playback and it advances the OFF state down the line of cans. Copy the effect 3 or 4 times and change the chase rate and put each on a playback and you can have different speeds of the "shadow". This also works on an LED strip light. By patching the strip as 12 indivdual fixtures (I use the generic 3 or 4 channel LED fixture) you can move your shadow (the OFF state) along the strip.

And then there's pixelmapping an LED array made out of 4' or 6' strips... but that is a little more complicated.

 

[mcdork]

Far be it from me to recommend non-technical solutions, but even if there's only a little bit of room in the wings why not have someone in a tree/telephone pole costume occasionally run across in front of the lights...

Frost the windows and soften the beams and it should work.

 

[zmb]

Far be it from me to recommend non-technical solutions, but even if there's only a little bit of room in the wings why not have someone in a tree/telephone pole costume occasionally run across in front of the lights...

Frost the windows and soften the beams and it should work.

Depending on how large the holes are, use some camo netting or something similar that would let some light through. Hang it on a rod above the window with some distance between the window and light source and have someone gently shake it back and forth.

 

[firewater88]

For a transition effect into a train bridge scene, we set up a light behind a box fan with a circular cut of matte board with random slots in it. Preset the fan to a low speed and then kick the light on. We were going for the look of car lights on the opposite side of the tracks as seen through the passing train. They were mounted in our box booms with an alternating red light going at the top.
Maybe this could be adapted to what you are doing, maybe multiple fans with different amounts of light able to pass, revolving at different speeds.

Or a rotating gobo in an I-Cue could be another option