National Geographic
The Invisible World
Public Approved
Name | Value |
---|---|
Code | adi-vid-01057 |
Title | National Geographic |
Subtitle | The Invisible World |
Description | ... |
Subject (keywords) | Performance Analysis ; |
Duration | 00:06:17 |
Created on | 10/21/2003 7:11:02 PM |
Label | Approved |
Privacy | Public |
Synopsis |
SynopsisThe human eye, despite its sensitivity and accuracy, has limitations. However, the advent of cameras and other visual instruments has expanded our vision and knowledge. The birth of photography in 1839 by Louis Daguerre was a revolutionary step, capturing images so detailed they seemed almost real. As photography evolved, it revealed things otherwise invisible to the naked eye. Edward Muybridge, in the 1870s, invented a way to record movements too quick to be seen, leading to the creation of the first motion pictures. Today, high-speed cameras and slow-motion films are used to analyze athletic performance. Dr. Gideon Ariel uses slow-motion film and computer analysis to study the dynamics of athletes' movements, providing coaches with objective, reliable information on body movement. This technology has helped athletes like Olympic discus thrower, Mack Wilkins, improve their performance and set new world records. Model Id: gpt-4-0613 |
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Though remarkably sensitive and accurate, the human eye is an extremely limited device,
a surprisingly narrow window on our world.
Today, as never before, cameras and other instruments that see are radically expanding
the limits of our vision and knowledge, and altering forever our image of the world.
Join us now on a visual journey beyond the limits of the naked eye on a voyage into the
invisible world.
I'm E.G. Marshall. In the winter of 1839, the public of Paris was astounded by a revolutionary
new invention. With metal plates made sensitive to light, and a simple box-shaped camera,
a painter named Louis Daguerre had created a collection of images so detailed and accurate
they seemed at first sight almost real. Photography had been born, and immediately it was hailed as
the miracle of its time. The earliest cameras took pictures of familiar things that the eye
could readily see. People and landscapes were favorite subjects. As photography grew more
sophisticated, the camera revealed an endless potential for ever greater miracles, for it could
be made to see things that were otherwise invisible. Through the specialized eyes of
cameras come new dimensions of seeing. Fleeting movement hidden by time, details shrouded by
distance and size, are revealed as vivid images which our eyes alone could never discern. But even
up close, our eyes can barely resolve objects that are one three hundredths of an inch in diameter.
With a microscope that filters the direction of incoming light, the composition of the physical
world can be vividly explored. Recorded on film at actual speed, we can witness the otherwise
invisible process known as crystallization. In a world of motion, there is infinite details
too fast for the unaided eye. In the 1870s, an ingenious photographer, Edward Muybridge, invented
a way to record movements normally too quick to be seen. A wager about the stride of a running horse
brought Muybridge to the stock form of a wealthy Californian. With a battery of 24 cameras that
were activated by threads stretched across a track, Muybridge captured aspects of motion that
had never been witnessed before. Muybridge's patron had bet that all four legs of a running
horse were sometimes simultaneously off the ground. Stop action photography proved him to be right.
By projecting his photographs in rapid succession, the first motion pictures were born. The movement
of people as well as animals became for Muybridge a passionate subject of study.
Much more than just a technical curiosity, Muybridge's pioneering work was the first
photographic analysis of the dynamics of physical motion. Today, modern high-speed cameras can record
rapid motion with a clarity that Edward Muybridge could only have dreamed of. Slow motion film is
now a commonplace tool in analyzing athletic performance. For Dr. Gideon Ariel, a physical
education expert and a former discus thrower on the Israeli Olympic team, slow motion film is just
the first step in the scientific coaching of athletes. Coaches used to think that by looking
on an athlete, they could tell what the athlete does right and what he does wrong. Later on,
they found out it's very complicated to start taking slow motion pictures. But we're finding
out and coaches finding out that even looking on a slow motion film, you cannot tell what is right
and what is wrong. The reason is that in any movement, it's not what we see with our eyes
that make the difference, but there are derivatives of what the eyes see, which is displacement,
velocities, accelerations, forces. We cannot see acceleration. We cannot see velocity. It might
appear fast, it might appear slow, but the relationship of one segment to the other in
the body, we cannot see with our eyes. Dr. Ariel has turned to the computer for aid in the analysis
of movement. Slow motion film of an athlete is projected frame by frame onto a recording screen.
Each touch of a sonic pen transmits into the computer memory the dynamically changing
positions of the athlete's joints and limbs. Human movement is governed by the same laws
of motion that apply to the entire physical world and from the visual information contained
in the film, the computer can rapidly calculate the interrelationship of force, acceleration,
and velocity in the athlete's movements.
Computer-created images combined with a mass of numerical data
can pinpoint where athletic technique is hindering performance.
So what coaches in the past thought they can see with the eyes, we're finding out you cannot do.
You have to quantify it. With the advent of computers, we can provide the coaches with much
more objective, reliable information on how the body move. Dr. Ariel's computer analysis of
Olympic discus thrower, Mack Wilkins, revealed that useful energy which would affect his throw
was being wasted on ground friction. Additional force was being spent by not rigidly planting
his forward leg at the moment of the throw. Based on this analysis, Wilkins altered his
throwing technique.
Several months later in international competition, he threw the discus over 13 feet farther than he
ever had before and set a new world record.