Anyone here ever built a large green screen? When I say large I'm talking 2-4 metres high, possibly 10 metres wide?

Reason I ask is because I have the mammoth task of building one, it needs to be big because apart from the actors everything will be plate-based. The shot takes place on the roof of a lofty skyscraper u see.

I got permission to film plates from a skyscraper but not actors due to safty and need some advice - how exaculy should I go about making it? I've made small ones before (1 metre tall, 2 metres wide).

well, you could always buy a couple of green sceens and link them together..but that would take some elaborate construction. Your best bet would be to use some sort of mono-chormatic big blanket-type-thing. lol. If I were you, I'd be worried about trying to light it correctly (and evenly) but that shouldn't be a problem if you're going to be using it indoors or in a studio.

well, for normal green screens people sometimes use bright green table cloths from a party store. you could make your large green screen the same way but with multiple table cloths. It wouldn't cost much, and it should be sufficient. If you have a wall large enough for what you need, you may want to set it up on that. otherwise you'll probably have to make some sort of frame out of PVC or wood. hope that helped.

Thanks guys, i'll have to check out those ideas.

Yeah a "wall-screen" seems best, and if its in doors all I have to worry about is cast shadows

I did, we rented a large green screen...but the difficult taks is to light it....it needs a LOT of light and also a strong backlight source for the actors to work properly

I just made a green screen myself for 15$ canadian. I already had a gallon of bright green flat/matte paint. I bought some 2x4's to make a frame and 2 4x8 sheets of masonite (home depot) they're super cheap, but you'll definately need help constructing it and transporting it. Works excellent!