depth

Question 1

What is depth perception?

Answer 1

The process of determining where objects are in space.

Question 2

What is Euclidian geometry?

Answer 2

Euclidian geometry: 
Parallel lines remain parallel.
Objects maintain the same size and shape as they move around.
etc.
The world follows these rules.
Images projected onto the retina do not!

Question 3

What are the two types of cues to an objects location in space?

Answer 3

monocular depth cues

binocular depth cues

Question 4

What is a metrical depth cue?

Answer 4

Provides quantitative information about an object’s distance in the third dimension.
Absolute metrical depth cues let you know exactly where an object is.

Question 5

What is a non metrical depth cue?

Answer 5

Provides information only about relative depth (rank order).

Question 6

What are the monocular depth cues?

Answer 6

Occlusion
Relative size
Relative height
Texture gradient
Familiar size

Aerial perspective
Linear perspective
Motion parallax
Accommodation
Convergence
Divergence

Question 7

What is occlusion?

Answer 7

When Object A obstructs the view of Object B, then A must be closer than B.

Question 8

What is relative size?

Answer 8

Items appear smaller when they are farther away from us

Question 9

What is relative height?

Answer 9

Objects higher in the visual field appear to be farther away.

Question 10

What is a texture gradient?

Answer 10

Lots of similar objects in the same image.
Closer objects will be larger and lower.
Distant objects will be smaller and higher.
This effect results from a combination of relative size and relative height.

Question 11

What is familiar size?

Answer 11

Determine distance based on knowledge of an object’s physical size.

Question 12

What is aerial perspective?

Answer 12

Thus, more distant objects appear fainter, bluer, and less distinct

Question 13

What is linear perspective?

Answer 13

Parallel lines will appear to converge as they extend into the distance in a two-dimensional image

Question 14

What is the vanishing point?

Answer 14

The apparent point at which parallel lines receding in depth converge.

Question 15

What is anamorphosis?

Answer 15

Use of the rules of linear perspective to create a two-dimensional image so it looks correct only when viewed from a particular angle.

Question 16

What is motion parallax?

Answer 16

Images closer to the observer appear to move faster across the visual field than more distant images.

Question 17

What are the eye based depth cues?

Answer 17

Accommodation: Lens focus
Convergence: Both eyes rotate inward to fixate on close objects.
Divergence: Both eyes rotate outward to fixate on distant objects.

Question 18

What is binocular summation?

Answer 18

The combination (or “summation”) of signals from each eye in ways that improve performance compared to just one eye.

Question 19

What is binocular disparity?

Answer 19

The differences between the two retinal images of the same scene.

Question 20

What is stereopsis?

Answer 20

Our vivid perception of being in a fully 3-dimensional world

Question 21

What is the horopter?

Answer 21

A circle of locations in the 3-D world.
Any object located on the circle will project an image onto corresponding points on both retinas.
Surface of zero disparity
Vieth–Müller circle: A similar concept.

Question 22

What happens when there is crossed disparity in front of the horopter?

Answer 22

Images in front of the horopter are displaced to the left in the right eye and to the right in the left eye.

Question 23

What happens when there is uncrossed disparity in front of the horopter?

Answer 23

Images behind the horopter are displaced to the right in the right eye and to the left in the left eye

Question 24

What is the relationship between Disparity and distance?

Answer 24

Bigger disparity means greater distance from the horopter.