vision and colour

Question 1

iris

Answer 1

controls how much light comes in

Question 2

lens

Answer 2

transmits incoming light to the retina adapting the focus nearer and farther

Question 3

retina

Answer 3

photoreceptor (light sensor) layer

Question 4

fovea

Answer 4

area of high density on the retina

Question 5

rods

Answer 5

sensitive to light intensity

Question 6

cones `

Answer 6

sensitive to light frequency

Question 7

what are the two types of photoreceptors

Answer 7

rods
cones

Question 8

central retina

Answer 8

only has cones
high density; perception of form
3 types of cones; colour perception

Question 9

short cones

Answer 9

blue light sensitivity

Question 10

peripheral retina

Answer 10

has more rods which detect light and motion

Question 11

medium cones

Answer 11

green light sensitivity

Question 12

long cones

Answer 12

red light sensitivity

Question 13

how do we see colour

Answer 13

cones get hit by light at a certain wavelength and the retina does minus calculations to convert that into a biological signal

Question 14

fovea vision

Answer 14

allows perception of detail
high resolution and colour sensitivity

Question 15

what is the degree for fovea vision

Answer 15

1-2

Question 16

what is the degree for peripheral vision

Answer 16

200 degrees left and right
130 degrees up and down

Question 17

how do peripheral and fovea vision operate together

Answer 17

in parallel

Question 18

peripheral vision

Answer 18

detection of stimuli; motion and light changes

Question 19

fixations

Answer 19

we move our eyes to align with objects of interest to get details

Question 20

how much time do we need for fixations

Answer 20

200ms before moving to the next fixation

Question 21

saccades

Answer 21

the fast movement between each fixation

Question 22

how much time do we need for saccades

Answer 22

20-30ms

Question 23

what is our viewing range without head movements

Answer 23

30 degrees down and 20 degrees left and right

Question 24

why do we need head movements when moving our eyes

Answer 24

helps us keep the eyes in a comfortable viewing range

Question 25

cyclopean model

Answer 25

whilst we have two eyes we never see two different images as theyre fused into one

Question 26

binocular model

Answer 26

our eyes are like two cameras at an offset from eachother

Question 27

what is binocular vision and what is it caused by

Answer 27

images from both eyes are slightly different parallax

Question 28

binocular disparity

Answer 28

the difference between both eyes gives a hint to the depth of an object

Question 29

vestibular

Answer 29

senses how much you rotate your head

Question 30

what causes simulator sickness

Answer 30

when theres a conflict between physical and visually percieved motion

Question 31

what gives us a sense of motion

Answer 31

when we move our heads a flow of light is created in the retina

Question 32

vergence

Answer 32

depending on the distance of the fixation the eyes turn towards eachother in the head so the lines of sight are aligned

Question 33

accommodation

Answer 33

eye lens changes shape to focus on an object with respect to the optics of the system

Question 34

what is the colour of an object

Answer 34

the wavelength of light that it doesnt absorb

Question 35

colour models

Answer 35

help us describe colours

Question 36

what are the 3 main colour models

Answer 36

rgb cmyk hsv

Question 37

cmyk

Answer 37

usually printers reflects only a set of frequencies key = black, dark/light, depth/shading

Question 38

hsv

Answer 38

hue; where it is on the spectrum saturation; purity, from grey to pure value; lightness/intensity

Question 39

how does contrast affect our perception

Answer 39

relative contrast can make colours look different