Document 391060

What are visual principles?
 Visual principles are ‘rules’ that we apply to visual
information to assist our organisation and
interpretation of information in consistent and
meaningful ways.
 Visual perception relies on three key principles to
organise information:
 Gestalt principles
 Perceptual constancies
 Depth Perception
Gestalt Principles
 It is believed that we organise stimuli into categories or
groups to understand them.
 The following are the categories we put visual
information into:
Figure-Ground organisation
Figure-ground organisation
 A stimulus appears to stand out (figure) against the
background (ground).
 We complete the gaps in a figure to view the stimulus
as a whole.
 We perceive objects that have similar features (size,
shape, colour) as belonging to a group.
 We perceive objects that are physically close together as
belonging to a group.
Perceptual Constancies
 Our ability to understand that an object’s size, shape,
brightness or orientation will stay the same even
though it has a different retinal image.
 Size constancy
 Shape constancy
 Brightness constancy
 Orientation constancy
Size Constancy
 Involves recognising that an object’s actual size
remains the same, even though the size it casts on the
retina changes.
Shape Constancy
 Is the tendency to perceive an object as maintaining its
shape despite any change in shape of the image on the
Brightness Constancy
 Is the tendency to perceive an object as maintaining its
level of brightness in relation to its surroundings,
despite changes in the amount of light being reflected
from the object on the retina.
Orientation Constancy
 Is the tendency to perceive an object as maintaining its
orientation despite any change in orientation of the
image on the retina.
Depth Perception
 Is the ability to accurately estimate the distance of
objects and therefore perceive the world in three
 Depth cues are sources of information from the
environment or from within our body that help us to
perceive how far away objects are.
Binocular Depth Cues
 Use both eyes to judge depth
 Convergence - inward turning of the eyes to focus on
nearby objects........try looking at the end of your nose
 Retinal disparity - the difference between the images of
both eyes....line an object up in the distance with your
finger. Try looking at this with the left eye and then the
right eye separately. What happens
Monocular Depth Cues
 Use one eye to judge depth
 Accommodation - the bulging and flattening of the eye to
 Pictorial Cues - found in pictures, drawings and photos.
Linear perspective
Texture gradient
Relative size
Height in the visual field
Linear Perspective
 Two lines that converge (come together) as they go into the
 An object that sits in front of / obscures another object
is perceived as being closer.
Relative size
 The object that has a smaller retinal image is seen as being
further away.
Texture Gradient
 An object that is further away from the person will
have less detail.
Height in the visual field
 An object that is closer to the horizon is seen as being
more distant.
More examples