Monocular / Psychological depth cues:

Linear perspective

Size of the image of an object on the retina changes in inverse proportion to its change in distance. Roads getting narrower as they vanish in to the distance, remember. See also: Emmert´s law.

Height in the field of view

Objects that rest on a surface below the horizon and are higher in the field of view are usually seen as beign more distant. Even if they are same size. See also: Emmert´s law,

Aerial perspective

Objects further away tend to become less distance, cloudy or hazy.

Interposition

One object occludes, hides or overlaps another.

Texture gradient

The pattern formed by a regular textured surface that extends away from the observer.

Color / Chromostereopsis

Fluids in the eye cause refraction. Reds appear closer than blues. Bright objects appear closer than dull ones.

Binocular / Physiological depth cues:

Accomodation

Change in focal length of the lens due to a change in tension from the ciliary muscle.

Convergence

Rotation of the eyes inward to focus on objects as they move closer to the observer.

Binocular disparity / Stereopsis

Difference in the images projected on the left and right eyes when viewing a 3D scene. See also: Horizontal parallax.

Motion parallax

As an observer moves, nearby objects appear to move rapidly while far objects appear to move more slowly.

Selected vocabulary

Emmert's law.

Size constancy:

The ratio of perceived size to perceived distance is constant for a given visual angle. Given the same retinal angle, B is perceived as smaller than A because B is perceived as closer than A.

The moral:

If you are going to have objects moving around in three dimensions in stereo, make sure they obey the laws of linear perspective. See also: Height in the field of view, Linear perspective.

Horizontal Parallax / Binocular disparity or Binocular parallax

When the retinal images of an object fall on disparate points on the two retinas. These points only differ in their horizontal position. Value given by R - L. Most important depth cue. See also:Binocular Disparity.

Stereo Window / Plane

The point at which there is no difference in parallax between the two eye views. Usually at the same depth as the monitor surface. See also: Zero parallax,Negative Parallax,Positive parallax.

Homologous Points

Points which correspond to each other in the separate eye views.

Interocular Distance

The distance between the left and right eyes. Usually about 65 mm. See also:Hyperstereo,Hypostereo.

Hypostereo / Giantism

Decreasing the distance between the left and right eyes to show stereoscopic detail on small items. Effect is like you would be a midget/child/insect. Choose your favourite one. See also: Hyperstereo, Interocular Distance.

Hyperstereo / Lilliputism

Increasing the distance between the left and right eyes to show stereoscopic detail in large scenes. Effect is like you would be a giant. See also: Hypostereo, Interocular Distance.

Positive Parallax

The point (i.e object in your picture) lies behind the stereo window. (On the opposite side from the observer.) See also:Zero parallax,Negative Parallax,Interocular distance.

Zero Parallax

The point (i.e object in your picture) is at the same depth as the stereo window. (Both eyes see the same image.) See also: Positive parallax, Negative parallax.

Negative Parallax

The point (i.e object in your picture) lies in front of the stereo window. (On the same side as the observer.) See also: Stereo Window, Positive parallax, Zero parallax.

Vertical Displacement

Vertical parallax between homologous points. See also: Homologous points.

Keystoning

Image warping, may be due to indirect projection. This is why you should have optical axes of your cameras parallel as you are taking or rendering stereopair pictures. See also: Convergence.

Interocular Crosstalk (Ghosting)