I hadn't seen that yet, no. Great find. Quite interesting. The footage of the guy looks quite creepy, though. I wonder if he looks that dusty in real life.
I believe the beam splitting technique is not actually two parallel cameras, but two cameras pointed at different angles at a mirror. The mirror is coated so that, at a certain angle, you can see straight through it, and at another angle, you see a reflection. So one camera just is pointed right at what you want to film, and the other camera gets the reflected image. It's precise enough so that there is no offset--it is effectively the same image. It's like how in an SLR camera, when you look through the eyepiece, you're seeing a reflection of what the lens sees, but it's an accurate indication of what will be recorded onto film.
This is the exact same technique that is used in modern 3D cameras, although they can adjust the horizontal offset to create varying degrees of the 3D effect. For the HDR photo/video, the offset is simply set to 0.
Thanks for posting this!
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