scene 1. Introduction to motion parallax

CLOSE UP: Dave's face describing what motion parallax is.

Dave:

Motion parallax, is the apparent shift of an object against the background that is caused by a change in the observer's position. Relative motion between the observer and the objects being observed in a visual scene leads to a deformation of the image on the retina, called optic flow.

Basically, when you are moving and you look at something with both eyes, the things closer to you move faster than the things that are farther away.  The two different angular images your eyes see, gives your brain cues to the depth of the field you are looking at.

Now here's something really cool. It's possible to extract 3-D information about scene geometry with one eye simply by feeding your brain cues that deform geometry that you are trained to perceive as three dimensions.

I know this sounds complex, but its not. Let me illustrate.

CLOSE UP: Dragon being moved back and forth to illustrate a 3-D object.

DAVE:

Doesn't this look like a three dimensional object? I'm moving it around and through one eye, the camera lens, it looks like it has mass. But, it's a gimmick.

CLOSE UP: Swivel the object to expose it's secret.

DAVE:

This is just a paper doll that's constructed so that you are looking at the inside of the structure. Since this is not something you normally you see, your mind tries to make sense of it and creates the 3-d illusion.