Homebrew 3D video projection

February 15, 2013 11:11 PM

Can I use polarizing filters with two aligned video projectors to make a 3D image that then can be viewed with Real3d / IMAX polarized eye-glasses?

I have this idea that if I got two polarizing filters to put in front of the light frustums coming out of two video projectors, then wore Real3D or IMAX goggles to view the image, the left eye would only see the light from the left projector and the right eye would only see light from the right projector.

But a friend of mine says that the moment the polarized light hits the wall, the photons will bounce away in every direction when coming off the wall, and no longer be polarized in a way that will let me use the 3D glasses to separate the images.

Is my idea feasible? Maybe not. Then how do 3D video projectors (the kind that cost $3000) work?

posted by shipbreaker to technology (5 answers total)

This project might be worth looking at.
posted by fearthehat at 11:25 PM on February 15

The key that makes it work is the metalized silver screen. Projecting on a white wall won't do it.
posted by zsazsa at 11:39 PM on February 15 [1 favorite]

Thank you both. The first link is absolutely spectacular, thank you.
posted by shipbreaker at 2:00 AM on February 16

My husband has a 3D projector setup in our house that uses two projectors. He recommends linear polarized filters and glasses rather than Real3D - it has less of a "ghosting" problem. His silver screen is white formica painted with Rusoleum aluminum paint.

He's got a tonne of details that I'm too slow to type out right now, but if you're interested in trying this out, send me a MeMail.

An important side effect of this setup is that he never wants to go to the movies ever, because his projection room isn't full of annoying strangers and he can drink beer there.
posted by jeoc at 12:42 PM on February 16

Low cost 3D projection using linear polarizing filters: Geowall Consortium. This is focused on classroom use, but obviously its not limited to that.
posted by bumpkin at 2:35 PM on February 16