Visual Perception -
Fundamental Processes
and Phenomena
John Sappington - john@basearts.com
|
Description: |
By exploring the phenomenology of human vision
and the nature of light in relation to the use/experience
of these phenomena-processes we develop a deeper or more insightful relationship
to the process of viewing as well as making visual art. We will take the
first half of the workshop to explore the fundamentals of light, color and
human
vision. In addition, we will experiment with our own vision in order
to better understand the workings of the systems that produce this sensory
experience as well as the limitations of the human visual system.
In the second half we will create
apparatus or devices that manipulate or alter our own vision. Through this
process we will investigate perception and how through vision we come to understand
and interpret art and the world. |
Reading List: |
"Vision and Art: The Biology of Seeing", Margaret Livingstone, 2002,
Harry N. Abrams, Inc.
"How to Use Your Eyes", James Elkins, 2000, Routledge
" Ways of Seeing", John Berger, ?
"another way of telling", John Berger, Jean
Mohr, ?
"Seeing & Writing 2", Donald McQuade / Christine McQuade, 2003,
Bedford/St. Martin's
---
"Vision and Visuality, Discussions in Contemporary Culture", editor Hal Foster, 1988, Bay Press
"Techniques of the Observer: On Vision and Modernity in the Nineteenth Century, Johnthan Curry, 1991,
Massachusetts Institute of Technology
"The Eye: The Seer and the Seen", Francis Huxley, 1990, Thames
and Hudson
---
"The Optics Book: Fun Experiments with Light, Vision & Color", Shar Levine &
Leslie
Johnstone, 1999, Sterling Publishing Co.
"Eye Popping Optical Illusions", Michael A. DiSpezio, 2002, Sterling
Publishing Co.
http://www.basearts.com/resources.html |
Resources: |
|
Schedule: example |
|
|
Lecture:
- How do we see & How does how we see affect what we are seeing?
- What exactly are we seeing?
- Define Vision
- Define Visual Perception
|
Nature
of Light
A light wave consists of energy in the form of electric and magnetic
fields. The fields vibrate at right angles to the direction of movement
of the wave, and at right angles to each other. Because light has both
electric and magnetic fields, it is also referred to as electromagnetic
radiation.
|
Topics:
Electromagnetic Spectrum
Electromag. energy
Particulate/Wave
Frequency/intensity
Incandecent / luminescent
|
Nature of Color
Light waves also come in many frequencies. The frequency is the number
of waves that pass a point in space during any time interval, usually
one second. It is measured in units of cycles (waves) per second, or
Hertz (Hz). The frequency of visible light is referred to as color, and
ranges from 430 trillion Hz, seen as red, to 750 trillion Hz, seen as
violet. Again, the full range of frequencies extends beyond the visible
spectrum, from less than one billion Hz, as in radio waves, to greater
than 3 billion billion Hz, as in gamma rays.
|
Topics:
Color Spectrum
Frequency
Nature of primary/complimentary
Reflective characteristics of surface / object
Experiments:
· Afterimages
· Prisms - glass/water/oil
· computer - gamut/ spectrum/sliders
|
Lenses - bending light rays/ virtual and real images
When light rays reach an angulated surface it causes the light rays
to bend. This is called refraction.
Light passing through a convex lens, the light rays bend toward the
center:
Light passing through a concave lens, the light rays bend away from
the center:
|
Topics/Experiments:
Obscura
Concave
Convex
Mirrors
Real / Virtual Images
Lens Elements in Cameras
|
Vision and the eye
When light enters the eye, it first passes through the
cornea, then the aqueous humor, lens and vitreous humor. Ultimately it
reaches the
retina, which is the light-sensing structure of the eye. The retina contains
two types of cells, called rods and cones. Rods handle vision in low
light, and cones handle color vision and detail. When light contacts
these two types of cells, a series of complex chemical reactions occurs.
The chemical that is formed (activated rhodopsin) creates electrical
impulses in the optic nerve. Rhodopsin is a mixture of a protein called
scotopsin and 11-cis-retinal -- the latter is derived from vitamin A
(which is why a lack of vitamin A causes vision problems). Rhodopsin
decomposes when it is exposed to light because light causes a physical
change in the 11-cis-retinal portion of the rhodopsin, changing it to
all-trans retinal. This first reaction takes only a few trillionths of
a second. The 11-cis-retinal is an angulated molecule, while all-trans
retinal is a straight molecule. This makes the chemical unstable. Rhodopsin
breaks down into several intermediate compounds, but eventually (in less
than a second) forms metarhodopsin II (activated rhodopsin). This chemical
causes electrical impulses that are transmitted to the brain and interpreted
as light.
|
Topics:
Vision - image or information
Components of the eye
Functions of rod/cone - pigments
Pupil
Fovea
Retina
Cone/Rod
Optic Nerve
Pathways of signals to and in the brain
Thalamus
Visual Cortex
Higher Level Processing
Periphery
Center/surround
exampleA
exampleB
· Perspective
· Depth/Distance
· Motion
· Contours
· Edges· edge enhancements
· Figure / ground
Experiments:
· blind spot
· depth perception
· Stereo Stereopsis
Persistence of Vision
· Zoetrope / phenakistoscope
· flip books / Finger animations
|
|
Introduction to Perceptual
Apparatus
The works that I am presenting express for me the proposition that a
work of art is not exclusively an object of passive observation (or the
6-10 second experience of an artists rendition of a pre perceived experience,
selection, documentation or framing but, a collaborative engagement and
attention to a physical, political, and/or cultural aspect of the world
that then potentially produces an aesthetic experience shared by both
the participant and the artist.
Our experiences or perceptions are influenced by what we are, how our
bodies function, our senses. The phenomenological processes at play in
our bodies and the universe as well as the neurological processes and
pathways transmitting sensory information form the basis of judgments,
opinions, ideas, memories and experiences.
As an artist, my primary concerns are perceptual experience and the
construction of meaning. By exploring the impact of altered or manipulated
vision through a series of optical devices constructed to restrict or
enhance the participants experience of seeing, this body of work invites
the viewer to consider what it means to see or generally to perceive
ones own experience through the work of art. By disrupting the visual
apparatus, my thought was that I am altering the relationship between
the perception, the means of perception and the stimulus thus altering
the point of view which opens the viewer to a new interpretation of their
surroundings and their experience. These optical forms operate as filters
between the participant / performer and experience.
In my own investigation of the limitations of static or representational
forms of art these optical devices provide a means to explore the relationship
between an experience or the memory of an experience and it’s translation
into a work of art.
|
|
|
Final Projects and Presentations: |
Visual Literacy
|
|
Additional Resources: |
|