Chapter 10 - Lecture Section 10.1

Question 1

What is a key challenge in perceiving depth?

Answer 1

A key challenge in perceiving depth is that we operate in a 3D world, different objects are different distances from us, and different distances from each other, but all of the visual information we are obtaining about those objects is coming from a 2d retinal image.

Question 2

What are Oculomotor Cues?

Answer 2

Oculomotor Cues are the sensation of eye position and accommodation

Question 3

What are Monocular Cues?

Answer 3

Monocular Cues require only one eye

Question 4

What are Binocular Cues?

Answer 4

Binocular Cues mean depending on two eyes

Question 5

Our perception of Depth from a 2D retinal image is based on ___.

Answer 5

Depth Cues

Question 6

Ocular Cues can also be performed with ___ eye(s), so they are a kind of ___ Depth Cue.

Answer 6

one // Monocular

Question 7

We feel the inward movement of our eyes using ___.

Answer 7

Proprioception

Question 8

What is Proprioception?

Answer 8

Proprioception is body sense, where we can detect the position of our body using sensory signals from the muscles.

Question 9

For a close object, there is a ___ amount of convergence, your eyes are pointing inwards towards your nose.

Answer 9

large

Question 10

For a distant object, where your eyes are basically pointing forward, there would be ___ convergence.

Answer 10

less

Question 11

Convergence is a ___.

Answer 11

Oculomotor Cue

Question 12

Accommodation is a ___.

Answer 12

Oculomotor Cue

Question 13

What is Accommodation?

Answer 13

In vision, bringing objects located at different distances into focus by changing the shape of the lens.

Question 14

As an object moves ___, the Ciliary body contracts which allows the Lens to round. This is an example of ___.

Answer 14

closer // Accommodation

Question 15

What is the tension you feel when you focus on your finger and bring it closer to your eye?

Answer 15

That is the Proprioceptive sense about what the muscles in your body are doing, and we can use this for depth information because the more accommodation, that means the closer the object will be.

Question 16

The more Accommodation, the ___ the object will be.

Answer 16

closer

Question 17

What are Pictorial Cues?

Answer 17

The type of cues that create the impression of depth from looking at pictures. This is the type of information that we obtain depth info from when we’re watching tv or looking at our phones.

Question 18

Pictorial Cues are a ___ Cue.

Answer 18

Monocular

Question 19

How did Renaissance artists create paintings with such a strong sense of depth?

Answer 19

Using Pictorial Cues

Question 20

What is Occlusion (Overlap)?

Answer 20

When one object hides another object, the hidden object is perceived as farther away

Question 21

Occlusion is a ___, ___ Cue

Answer 21

Monocular // Pictorial

Question 22

Relative Height is a ___, ___ Cue

Answer 22

Monocular // Pictorial

Question 23

For Relative Height, generally, it follows the rule that objects that are closer to where the horizon is in the picture, are perceived as ___.

Answer 23

farther away

Question 24

For Relative Height, objects that are below the horizon, the object that is higher and closer to the horizon is perceived as ___. The object that is lower in the image is perceived as ___.

Answer 24

farther // closer

Question 25

In Relative Height, for objects that are above the horizon, such as two clouds, the one that is closer to the horizon is perceived as ___. The cloud that is farther away from the horizon and higher up is perceived as ___.

Answer 25

farther away // closer

Question 26

What is Familiar Size?

Answer 26

Familiar Size helps in judging distance based on prior knowledge of the size of objects.

Question 27

Familiar Size is a ___, ___ Cue

Answer 27

Monocular // Pictorial

Question 28

Kakes use of ___ about the size of familiar objects helps in judging the depth based on how the objects will change in size if they are closer or farther from you.

Answer 28

Top-Down information

Question 29

How did Epstein (1965) measure subjects' Familiar Size?

Answer 29

Epstein (1965) had subjects view either normal coins or pictures of coins that all had the same size, subjects closed one eye, using Monocular vision.

Question 30

What did Epstein notice in the Dark-room condition, where coins were illuminated by spotlight?

Answer 30

Subjects perceived the Dime as the closest; the Nickel as far; and the Quarter as the farthest

Question 31

Why did subjects perceive the Dime as the closest; the Nickel as far; and the Quarter as the farthest in the Dark-room conditions?

Answer 31

This is because if the Dime ends up being closer to you, it takes up a larger portion of your visual field, so people were using their understanding of how large dimes, quarters, and nickels usually are to get this percept. Its a fairly weak illusion though, because when you have a lit room, and you're allowed to use 2 eyes, instead, you actually just perceive oddly sized coins that are all the same distance away.

Question 32

What did Epstein notice in the Light-room condition, where coins were illuminated by spotlight?

Answer 32

Subjects perceived oddly sized coins that were all at the same distance away

Question 33

Relative Size is a ___, ___ Cue

Answer 33

Monocular // Pictorial

Question 34

What is Relative Size?

Answer 34

When two objects are of equal size, the farther object will take up less of your field of view

Question 35

What objects does Relative Size not work on?

Answer 35

Relative Size doesn't work for objects that you don't have a good sense of their size Example: Clouds, they could be any size and they don't come in a consistent size.

Question 36

What is an example of Relative Size?

Answer 36

You see two motorcycles driving down the road, you know that motorcycles are generally about the same size, so the object that takes up less of your field of view is perceived as farther away.

Question 37

Perspective Convergence is a ___, ___ Cue

Answer 37

Monocular // Pictorial

Question 38

What is Perspective Convergence?

Answer 38

Parallel lines converge as distance increases.

Question 39

Which cue particularly applies to parallel lines?

Answer 39

Perspective Convergence

Question 40

When the parallel lines are farther away from one another, that section of the road is ___, and when the lines are closer together, that is the portion of the road is ___.

Answer 40

closer // further away

Question 41

Atmospheric Perspective is a ___, ___ Cue

Answer 41

Monocular // Pictorial

Question 42

What is Atmospheric Perspective?

Answer 42

Atmospheric Perspective is a result of air (dust, H20 droplets, pollution) filters and scattering light. Therefore distant objects appear less sharp (lower contrast), and tinted blue.

Question 43

A very distant object with a lot of air between the observer and the object is going to appear ___, in other words it will have lower contrast or be a little blurry, and it's going to be slightly tinted ___.

Answer 43

less sharp // blue

Question 44

A man is looking out over a forested coast, what does he notice about the colour of the trees?

Answer 44

The trees closest to the man are a deep, rich green, and there is a deep contrast for the shadowed part of the trees. But as he looks farther and farther out, he sees that they become lower contrast and slightly tinted blue.

Question 45

Where might you not find Atmospheric Perspective?

Answer 45

Without atmosphere there would be no atmospheric perspective, so on the Moon this depth cue does not exist

Question 46

Why can your Atmospheric Perspective be dependant on where you live?

Answer 46

Because the Atmosphere is different in different types of areas. Large cities have air that is dirtier, therefore thick and smoggy, whilst the air in the wilderness is more clean.

Question 47

A man from the city who is used to smoggy air may see a mountain in a forest as being ___ than it really is because he is calibrated based on the Atmospheric Perspective he's used to using in a smoggy city.

Answer 47

closer

Question 48

Texture Gradient is a ___, ___ Cue

Answer 48

Monocular // Pictorial

Question 49

What is Texture Gradient?

Answer 49

Textures appear more closely packed as distance increases

Question 50

In order for a Texture Gradient cue to work, you have to be fairly familiar with what is making up the ___, so you know that it is a ___.

Answer 50

texture // consistent size

Question 51

What types of things does Texture Gradient work on?

Answer 51

Texture Gradient works with groups of humans, flowers, and regular elements in the environment

Question 52

Shadows are a ___, ___ Cue

Answer 52

Monocular // Pictorial

Question 53

What do Shadows serve as?

Answer 53

Shadows can provide depth information about the position of a light source, but also depth within an image and depth within an object.

Question 54

What is an example of Shadows at work in an environment?

Answer 54

Two pictures of the same mountain taken at different times of day can create different perceptions, where in the first image the angle of the sun is creating deep shadows and we can see the ridges and hills, and get a strong sense of depth of the different parts of this mountain. But in the second image, without shadows, the mountain looks quite flat and homogenous.

Question 55

Shadow can ___ the position of different objects within a scene.

Answer 55

disambiguate

Question 56

How do some artists create unique shapes only visible when viewed from the right/particular location (e.g. Felice Varini)?

Answer 56

Using knowledge of perspective, pictorial depth cues, and the Inverse Projection problem They appear to violate regular depth coding.

Question 57

Chalk artists often make use of ___ to provide the impression of depth to their work by laying the chalk down on the street in a distorted way to create the impression of depth.

Answer 57

pictorial depth cues

Question 58

How does Motion work to create depth?

Answer 58

Motion works because as you move through the environment, you can look with just one eye and these motion cues are also gonna help you with depth perception.

Question 59

Pictorial depth cues work when the observer is ___.

Answer 59

stationary

Question 60

Motion is a ___ Cue.

Answer 60

Monocular

Question 61

When the observer ___, even more depth cues are available.

Answer 61

moves

Question 62

Motion Parallax is a ___, ___ Cue

Answer 62

Monocular // Motion

Question 63

What is Motion Parallax?

Answer 63

When an observer moves, objects nearer to the fixation point/place they are looking at appear to move slower

Question 64

To get a sense of ___ of the retinal image moving across the retina, we can calculate Velocity

Answer 64

speed

Question 65

Velocity = ___?

Answer 65

Distance/Time

Question 66

*IDK if this is written entirely correctly, refer to slide titled "2. Monocular Cues (Motion) "* An image that travels a large distance over the Retina as the observer moves down is perceived as a ___.

Answer 66

high Velocity

Question 67

*IDK if this is written entirely correctly, refer to slide titled "2. Monocular Cues (Motion)"* An image that travels a shorter distance over the Retina as the observer moves down appears to be moving ___.

Answer 67

slower

Question 68

For the Moving Observer - Motion Parallax follows the general rule that near objects appear to move ___.

Answer 68

faster

Question 69

For the Moving Observer - Motion Parallax follows the general rule that near objects appear to move ___.

Answer 69

faster

Question 70

For the Moving Observer - Motion Parallax follows the rule that when the observer fixates on the horizon, near objects move ___.

Answer 70

faster

Question 71

For the Moving Observer - Motion Parallax follows the rule that when the observer fixates on an object (the object = stationary), other stuff that is closer moves in ___ direction as the observer.

Answer 71

opposite

Question 72

For the Moving Observer - Motion Parallax follows the rule that when the observer fixates on an object (the object = stationary), other stuff that is farther moves in the ___ direction as the observer.

Answer 72

same

Question 73

*Questioning if this is correct, rewatch lecture* In Motion Parallax, things that are very close to the fixation point, but are closer than the fixation point will move in the ___ direction as the observer.

Answer 73

opposite

Question 74

*Questioning if this is correct, rewatch lecture* In Motion Parallax, stuff close to the fixation point is gonna move ___ and stuff far from the fixation point is gonna move ___.

Answer 74

slow // fast

Question 75

Deletion/Accretion is a ___, ___ Cue.

Answer 75

Monocular // Motion

Question 76

What is Deletion/Accretion?

Answer 76

This is when you are moving in the environment and you see two objects, one is occluding the other, and you move, changing the perspective.

Question 77

What is Deletion?

Answer 77

When you are moving in the environment and you see two objects, one is occluding the other, and you move and the near object appears to block the view of the far object, this is referred to as Deletion.

Question 78

What is Accretion?

Answer 78

When you are moving in the environment and you see two objects, the near one occluding the far one, and you move, uncovering the occluded far object, this is referred to as Accretion.

Question 79

What is the purpose of Deletion/Accretion?

Answer 79

We can use Deletion/Accretion as a way of getting depth information because the thing that is being Deleted or Accreted is always further away, so it's just occlusion, but with motion added to it.

Question 80

Deletion/Accretion is the dynamic example of ___.

Answer 80

Occlusion

Question 81

There is no ___ depth cue.

Answer 81

perfect

Question 82

True or False: All depth cues work equally well

Answer 82

False. Some work at certain distances much better than others.

Question 83

Which depth cue essentially always works?

Answer 83

Occlusion essentially always works because the object that's covering another one is always closer

Question 84

For ___ and ___, those proprioceptive signals are only good for large differences in the contraction of your muscles, so they are only good for 0-2 meters, and everything past that, the difference is so small that it becomes undetectable, only good for close up stuff.

Answer 84

Accommodation // Convergence

Question 85

___ is a fairly reliable depth cue

Answer 85

Relative Size

Question 86

Motion Parallax is good for things that are ___ to you, but when you have a very distant horizon in a very open setting, a high degree of openness, the things that are really far away appear to be moving so slowly relative to each other that they appear stationary.

Answer 86

fairly close

Question 87

___ is only good for fairly distant things, not things that are right up close to you.

Answer 87

Relative Height

Question 88

___ is only useful for very distant objects.

Answer 88

Atmospheric Perspective

Question 89

Which depth cues are only effective for 0-2 meters in front of you?

Answer 89

Accommodation & Convergence