Building a tunnel of diffusion

[Jakob Webb]

I want to build a tunnel for a short film I am creating.

It would be made out of a white fabric, such as cotton. The tunnel would need to be 4M X 8M big, but I’m not quite sure where you can buy fabric this big, since fabric is usually only 2 metres wide.

I’m going to be shining light through it, so it will also act as diffusion. As a backup idea I was thinking maybe I could have 2 long walls of fabric, like a sort of hallway, but I would quite like to show the top of the tunnel.

Does anyone have any ideas on how I can make this fabric tunnel / where I can buy a wide piece of white fabric?

Topic

[Al Duffield]

If you live near the ocean or other big body of water, look for a sail maker. They’re experienced in joining large sheets of fabric together and will happily do the job for you. Assuming you don’t have any set builders you can go to.

[quijotesco24]

There are indeed really big fabrics sellers if that’s what you need. The highest I’ve bought was 6 wide meter roll and the roll was like hundreds of meters long. But I know there was even wider than that. But it gets really expensive. So for massive pieces you will end up stitching.

Your best bet will be companies that deal with fabrics exclusively for stage purposes. You know, for big theaters, opera houses, music halls.

Also most of the fabrics these companies deal are already fire retardant treated, there are some heavy regulations about what fabric ends on a Stage, something you really need depending which lights you will be using.

 

[Stip]

What is holding the tunnel? If you sew several pieces together you could hide the seam near the scaffold. Lighting from outside could help to hide the seams too depending on the intensity of light and thickness of fabric.

[Jakob Webb]

I was going to use 2 backdrop stands (placed at opposite ends) and maybe a boom arm in a grip head to support the middle and then just clamp the cloth to it.

Not sure if the cloth will be too heavy though, do you have any suggestions for how to support it?

[The Byre]

Does it HAVE to be cloth?  How about sheets of plastic/PVC?  Admittedly, they will not pass & health and safety rules for a regulated union shoot, but if the is an ‘informal’ gig, I would go down the PVC route.

You can also get 8′ x 4′ PVC sheets that will pass H&S rules (fire retardant, etc.) that are used in hospitals and commercial kitchens.  8′ is the standard ceiling height.

White and clear PVC on a roll costs (UK) about £30 for a 4m x 8m length on eBay.

There are all sorts of funky materials for you to play with and get creative about!

[Roger Deakins]

You could make hoops of 1″ plastic pipe to hold up a ‘tunnel’ of diffusion. There is a white industrial plastic that is equivalent to a 216 diffusion and comes in a wide roll. I used this on a film when I needed a lot of diffusion, instead of paying far more for something from a film supply company. You could rent seamless grid cloths or silks, which might be the cheapest option.

[LucaM]

Roger Deakins wrote:

You could make hoops of 1″ plastic pipe to hold up a ‘tunnel’ of diffusion. There is a white industrial plastic that is equivalent to a 216 diffusion and comes in a wide roll. I used this on a film when I needed a lot of diffusion, instead of paying far more for something from a film supply company. You could rent seamless grid cloths or silks, which might be the cheapest option.

It’s comforting to know that even you resort to a bit of DIY for some scene. 🙂

[Jakob Webb]

Thanks for replying Roger! I managed to find some white tarpaulin that is the right size, but I’m not sure how much light will be cut out when using this as diffusion.

Do you know what the industrial plastic you mentioned is called?

 

[Roger Deakins]

I don’t remember the specific material. I used it on ‘Shawshank’ so that was a long time ago. Tarp might well be too dense but that will depend on what lights you have. What I was thinking of was equivalent to a 216 or even less dense than that.

[Author]

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