The Persistence of Vision

Science Behind the Birth of Film
Examples
I can see clearly now!
by Katelyn Markham
Persistence of Vision
All films are based on the concept


an image is retained in the retina for approximately 1/25th of a second after the image has disappeared.




imagine looking at the sun

close your eyes

you will see a dark afterimage

That's the persistence of vision!

discovered by Aristotle 300 B.C.
Motion Perception
Phi Phenomenon
Beta Movement
the apparent movement between images that succeed one another rapidly
when the brain combines 2 or more images to perceive motion
Due to the Beta movement, these two images appear to be in motion.
In fact, this clip is only two images, one with a large ball, another with a smaller.
here are two concepts that support the persistence of vision
Phi Phenomenon is based on the illusion of
closure
when a person watches a film, the intervals between rapidly projected still- pictures are filled
This is a 2 sec clip with about 27 frames.
Notice that it looks like a moving picture. This is Persistence of Vision at work!
Woah! Is that ball is getting closer?
Most digital video cameras capture 24 frames per second
Classic silent films use approximately 16 frames per second
with
How about some History!
Cartoons project one drawing for every two frames which is about 12 drawings per second
An audience relies on their
persistence of vision
to perceive motion in framing techniques less than 24 frames per second.
History of Beta Movement
History of Phi Phenomenon
Without the Persistence of Vision and it's 2 defining concepts

1. We'd be blind
2. No movies :(
My Example!
Bibliography
Britannica.com "History of the Motion Picture"
Psycology.wikia.com/Beta-Movement
Wikipedia.org
Here is an abstract film I created with the concepts of
persistence of vision.
You will notice motion to be choppy, however as the Phi phenomenon and Beta Movement work together, these images will appear to be moving, like a true motion picture.
This film was made with about 700 individual photographs strung together for the perception of motion, and it's only 3 minutes long!
ENJOY(:
Ptolemy had not founded this theory. Instead he theorized concepts that lead to the true Persistence of Vision Theory!
For example:
perceivable distance based on sizes and shapes
distinction of illusion caused by physical or optical factors
Over the course of many years, new discoveries were made about optics and vision of motion
In 1824
Peter Mark Roget
wrote an "Explanation of an Optical Deception in the Appearance of Spokes of a Wheel When Seen Through Vertical Apertures."
His stroboscopic tests with lights and optics lead to early inventions of illusions of movement.
In 1831 Dr. Antoine and Dr Rittrer created an illusion of movement by placing slightly different images in small windows of a rotating disk, called the
Phenakitstoscope.
This lead to the invention of Thomas Edison's Kinetoscope.
Sound Familar??
Insert the DVD!!
"A Burning Memory"
by Katelyn Markham
Princeton.edu "Persistence of Vision"
Dictionary.reference.com
Joshuamosley.com "Compiled Animation History"
The discovery of the phenomenon of motion perception has allowed for the engineering of the videocameras and film.

With the knowledge of how long an image (or light) is sustained in the retina, filmmakers figured out how many frames to take in order to make it seem like images are moving.