What's the fuss with 3D imagery?

Humans have stereoscopic vision. We have two laterally-displaced eyes, and the slight differences between the left-eye and right-eye images are processed by the brain to furnish us with a sense of depth perception.

This is the natural way in which we view the world, and we intuitively use that direct depth perception as an aid to our interpretation of the world. By definition, it requires the brain to be provided with two separate images- two views of the same scene, differing due to the different locations of the imaging systems (our eyes). Most artificial scenes- be they drawings, paintings, photographs, TV screens, computer monitors- present the eyes with a single image only. Although we view that "scene object" with both eyes, there is no sterescopic imformation within that scene object. It is "flat", since both eyes see essentially an identical image of that scene object, and there is no information therein for the direct perception of depth (although other clues, such as object occlusion and lighting effects in that artificial scene are interpreted so as to provide some depth information).

Thus, in the viewing of these monoscopic artificial scenes, we are missing out on a rich source of visual information that we take for granted when viewing the natural world. What we're concerned with here is the attempt to introduce natural depth perception (stereopsis) into such artificial scenes- to imbue such scenes with a greater amount of the visual richness that we use as a matter of course in our day-to-day view of the world.

To achieve this, we must first acquire or generate the image pairs that are required. This may involve capturing real world content (i.e. photography or filming of real world scenes) or computer-generated or other artificial content- or, indeed, the combination of these.

We will look at such acquisition in the next FAQ item.