Is This Possible???

[kevinz]

At the end of the Summer, my high school is putting on the show "20th Century". For those unaware of the plot, it is set on a train. The set will consist of two train cars on stage with windows in each car. My technical director thinks it would be a good idea to project moving scenery onto a cyc behind the train so that it looks like the train is moving if you look through the windows. The set spans just about 32 feet across, and my TD is opposed to using multiple projectors. I was wondering if anyone new a good way to accomplish this.

[sk8rsdad]

Without knowing the geometry of your set and stage it is not possible to provide anything but suggestions as to what might work or whether it is feasible in your space.

Assuming you have a decent projector and the right lenses it is possible to cover both screens using rear projection with a single projector.

Assuming you do not have that option, then it can be done with two consumer-grade projectors, Q-Lab 2 (or something like it) and a PC or Mac that supports dual monitors, especially if the seam where the 2 images meet is not visible to the audience.

You could also use something like the GAM Film-FX, or painted scenics on a reel, or make the windows translucent and blink some lights on a slow random chase to give the impression that you are going past some street lights, or buildings.

[kevinz]

Thanks a lot.

[NickJones]

Anything is possible.
(I really hate those inspiring posters, t-shirts, wallpapers that say stuff like that, if your self esteem is so low you thing a t-shirt can cheer you up, you have problems)

Firstly rear projection, if there is enough room behind your cyc it can be possible to project from behind. That's your best bet, but as to the distance between the wall and the Cyc, you need a lot to get an image that size.

It is possible to tile your screens so you set up your laptop to have a 800x5000 resolution and it splits it up into 4 or so different VGA outputs. This may cost a lot, but they are very cool. It stretches your image out into the different outputs. I read about this on a site that is down at the moment, I can find the info on it if you want, from memory it was around $400 US. But considering you are on a high school budget you might be better just to have the same video playing on each. Simply by using multiple projectors and a distribution amp. The chances of your Cyc being far enough away and projectable (is that a word?) is slim. So you probably would need multiple projectors.

Nick

[porkchop]

I'm gonna jump on the bandwagon of have your TD reconsider multiple projectors. Here's a short list of reasons why I think one projector is a bad idea:

• To get a projector and lens setup that could project that size at any decent resolution and with any brightness at all will likely be expensive, probably very expensive.
  
• Since it's only two windows you're probably paying for a lot of projection that you simple don't care about (i.e. all the cyc that is being projected on that can't be seen by the audience). Even if you're not putting something in that space you're still paying to project there.
  
• The space required is going to be difficult to achieve. For an idea of what I'm talking about we projected on a 40'x 15' screen and had to have our projectors 50' back from the screen. This space can be minimized in some ways (mirrors, different lenses, etc...) but how much space do you have for this?
  
• Either you pre-production editing is going to have to be very interesting (read time consuming). Or your going to have to be very crafty with how you block anything that's being projected from being seen outside the windows. For example any space between the train cars.
  
• Big projectors tend to take big power, ours took 50 amp three phase. It would be a bummer to get the projector to the venue and go "how are we gonna plug this thing in"

Basically anything IS possible but I don't think this is the way to go about it here is a list of reasons I would use two projectors:

• The two projector solution allows you to use much smaller and cheaper projectors. If your lucky your school may even have two desk top projectors that you could use for the show.
  
• You could use the same video on each projector just run the one for the forward car a second or so (obviously this would require testing a tweaking) ahead of the other one. This makes editing easier.
  
• There's no worries about projecting something in places you don't want projection, as is a possibility I mentioned on the one projector list.
  
• You are way more likely to have the space for two smaller projectors.
  
• If for some reason one projector doesn't work you can have that window covered by drapes or something like that and still have the effect in the other window as apposed to doing all that work and getting nothing if something goes wrong on the one projector model.
  
• Smaller projectors can be powered off a standard wall outlet which I bet you have a few of in the space.

One additional thought rear projection would allow you to keep the cyc closer to the train cars so you don't require as big of a projected image, but remember it's a cyc not a rear projection screen. Try it out before you commit to a design because you might have to project from the front to allow the images to be seen.

[museav]

A totally different approach if the windows are small enough would be to use a flat panel display for each window. If you just want some sense of movement you could send the same signal to each or you could get fancier and use external processing to send a part of a larger overall image to each display.

[TheSwami]

Another totally different approach would be to take a 64'+ long piece of canvas/muslim/bedsheets sewn together, sew it together to make a long "conveyor belt" of cloth, and paint one continuous scene onto it. Then slip it over a drive cylinder/metal pole/number of coffee cans stuck together on either end and power it either with a high-torque motor or human power, whichever is simpler.

This is an entirely serious suggestion: In a high school environment, where labor is plentiful and money is not, sometimes simplifying a project and scaling it up is the best option. Can't afford castors for the set pieces? Get more run crew, carry the things off. Can't afford crackle glaze? The Intro the Theatre class spends a day and four gallons of paint learning how to texture a set. Excitable manpower can be a great asset in this kind of environment.

73

[NickJones]

The roll idea would be risky I presume as it has a lot more chance to snap.
If you can get your hands on a selection of computer screens/TVs then you could use distrobution amplifier to get video to each of the TVs, and then just stick them behind the window.
Nick

[Chris Chapman]

It depends on the amount of tension on the roll. For a low tech solution where projectors and multi-media are out of the questions this actually may be the way to go. It worked for the 17th through the 19th century fine.

[gafftaper]

The roll idea has worked for a couple hundred years... it'll still work today.


As for the original question:

Since it's a school the easy answer is just get a small classroom size projector for each window. They just aren't bright enough to do it all in one. But they'll be perfect if only doing one small window.