Mono: Lightness

Question 1

What are the 4 things that light reaching the eye from a surface depends on?

Answer 1

1. The albedo of the surface
2. The Illumination
3. Geometry of the surface
4. Transmitting medium between the reflecting surface and the eye

Question 2

The Reflectance of a surface is a measure of how it __________ light.

Answer 2

Reflects

Question 3

The intensity of reflected light is called _____________.

Answer 3

Luminance

Question 4

Luminance is affected by both _________ and ___________.

Answer 4

Reflectance and intensity of incident illumination

Question 5

Observers perception of surface Reflectance is termed _____________.

Answer 5

Lightness

Question 6

What are the 4 optical phenomena regarding natural vision?

Answer 6

1. Diffuse reflection (lightness)
2. Specular Reflection (shininess)
3. Appearance of Transparency
4. Appearance of Translucency

Question 7

When a beam of light strikes a matte surface, the reflected rays are __________ scattered in what direction?

Answer 7

Diffusely scattered in all possible directions

Question 8

When a beam of light strikes a shiny surface, how is it reflected?

Answer 8

With little or no scattering

Question 9

Specular reflections at any given surface location are visible only from a __________ set of possible vantage points.

Answer 9

Limited

Question 10

When a beam of light strikes a transparent material, it is ___________.

Answer 10

Transmitted through it

Question 11

What causes the apparent distortion of a tile floor if viewed through a curved glass?

Answer 11

Refraction

Question 12

Translucent surfaces transmit light but what happens to the light?

Answer 12

It is scattered randomly in different directions

Question 13

The appearance of lightness may be based only on the _________ component of surface Reflectance.

Answer 13

Diffuse

Question 14

The specular components of surface Reflectance are _______________ in the perceptual analysis of lightness.

Answer 14

Discontinued

Question 15

Lightness is the perceptual dimension that runs from ________, through _______, to __________.

Answer 15

Black, through Gray, to White

Question 16

The permanent property of a surface that determines what % of light that surface reflects is what counterpart of lightness?

Answer 16

The physical counterpart of lightness

Question 17

Lightness is perceived ______________.

Answer 17

Reflectance

Question 18

Perception of surface lightness allows us to differentiate and identify what two things?

Answer 18

Differentiate one surface from another but also identify real-world properties of a particular surface

Question 19

What is the ability to recognize that surfaces under different illuminations have the same Reflectance?

Answer 19

Lightness constancy

Question 20

Two equal-in-luminance patches can appear different in lightness when set against different ________________.

Answer 20

Backgrounds

Question 21

For silver, illumination is reflected at __________ incidence angles.

Answer 21

All

Question 22

For glass, illumination is reflected at _________ incidence angles.

Answer 22

High

Question 23

Brightness is the perceptual dimension that runs from ________ to ________.

Answer 23

Dim to bright

Question 24

The physical counterpart of brightness is called ___________.

Answer 24

Luminance

Question 25

Brightness is perceived ___________.

Answer 25

Luminance

Question 26

Lightness concerns the ______ side of visual experience while brightness concerns the _________ side.

Answer 26

Objective ## Footnote Subjective

Question 27

Brightness is our experience of the raw ___________ emanating from a surface.

Answer 27

Raw energy

Question 28

Perceptual dimension of lightness?

Answer 28

Black to white

Question 29

Perceptual dimension of Brightness?

Answer 29

Dim to Bright

Question 30

Physical counterpart of Lightness?

Answer 30

Reflectance

Question 31

Physical counterpart of Brightness?

Answer 31

Luminance

Question 32

Is lightness permanent or transient?

Answer 32

Permanent

Question 33

Is brightness permanent or transient?

Answer 33

Transient

Question 34

While brightness is raw energy, lightness is the ____________.

Answer 34

Proportion?

Question 35

Lightness and brightness are encoded where at in the eye and brain?

Answer 35

Retina and cortex

Question 36

Activity in early visual-cortical areas correlates with the __________ rather than physical properties of the visual stimuli.

Answer 36

Perceived