Building a tunnel of diffusion

Jakob Webb · March 20, 2023

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.

Also in terms of supporting it; I was going to use 2 backdrop stands at each end and maybe a grip arm in the middle (the fabric would be clamped to these). But does anyone have any other budget friendly ideas for how to support it?

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

Mark Dunn · March 20, 2023

If you form the fabric into a spiral, there's no limit to the size except the practicality of handling. Support could be canes steamed and joined into rings, like a sort of huge china ball, or even a spiral, like the material itself. A spiral may be self-supporting to some extent.

Edited March 20, 2023 by Mark Dunn

Jakob Webb · March 21, 2023

@Mark Dunn That's a great idea! When you say canes, what do you mean? If you mean bamboo canes, I'm not sure how to bend those.

Mark Dunn · March 21, 2023

I'm thinking of something we used to hang a quilt. It doesn't look like what we usually call bamboo, but it may be the heart wood from it- looks like this

https://www.amazon.co.uk/Green-Flower-Sticks-Cane-Support/dp/B00N4ZM7DQ/ref=sr_1_51?keywords=Canes&qid=1679396045&sr=8-51

I think you'd want them as long as you could get, steam in a curve and join them with tape or ferrules. Just an idea, it's not something I've tried.

Wire might work if you can buy it coiled. But I think wood would be easier to work with.

Edited March 21, 2023 by Mark Dunn

Frank Wylie · March 25, 2023

Most fabric stores carry a fabric to stiffen shirt collars that is heat resistant and looks very much like a thicker tough spun light diffusion material.

It's also a lot cheaper than tough spun...