(Part 2 of a series)
Just how does one get a still picture to move? And who
figured out how to do it?
If I could go back in
time and ask these questions, we’d hear an international chorus of me, me, moi,
moi, as Englishman Eadweard Muybridge, American Thomas Edison, and Frenchmen,
Louis LePrince and Louis Lumiere all raise their hands frantically. And they all own a piece of the answer, for
no single inventor could have done it without looking at the ideas of the
others.
In the next two posts we’ll confine our discussion to
Muybridge and Edison for it is their inventions that are in direct line with
what we call the video camera today. And it is also amusing to note that
judging from the lives they lived, neither one of these pioneers of moving
images was able to sit still for long.
Before we start though, let’s keep in mind that a movie
camera, (and an IP camera) is nothing more than a camera that captures many
images in sequence and records them on media. What sets the images in motion?
Your brain.
We are only able to process individual frames if presented
to us at a maximum of 12 per second. Our brains hold these images for about
1/15 of a second. So if frames are
presented at 15 per second or faster, we will perceive them as continuous
motion. Early movies, or moving pictures, as they were rightly called had a frame
rate of 14 to 24 images per second.
With that basic concept in mind, our previous post, Before the Video Camera: First Steps, looked at Muybridge’s contributions, let’s see
what Edison added.
Thomas Edison
Young Thomas Edison was home-schooled after twelve weeks in
a one room schoolhouse with thirty eight other youngsters spread across grade
levels. The sole teacher had little patience with the six year old’s
unquenchable curiosity and endless string of questions.
Educators of today
might label him as having ADHD (Attention Deficit, Hyper Active Disorder). And
indeed his checkerboard of early jobs does point in that direction. Peripatetic
as he was, though, he never left a field without improving on its tools.
Prior to becoming involved in the moving picture quest,
Edison had already left an impressive trail of inventions.
- The automatic repeater – a device for transmitting telegraph signals between unmanned stations which ultimately allowed telegraphers to translate code at their own speed and convenience.
- The quadriplex transmitter which allowed the transmission of telegraph signals over multiple frequencies
- The carbon transmitter which improved audibility of Alexander Graham Bell’s telephone
- An improved stock-ticker
- An electric vote recording machine
His more well-known inventions include
AND
By 1887, Edison recognized the need to consolidate operations. He
and his growing team of assistants moved into a building in West Orange, NJ,
establishing what some call the first research and development lab.
In 1888, Edward Muybridge visited with his zoopraxiscope and
a proposal for Edison. Why not combine
the zoopraxiscope and the phonograph? Initially, Edison liked the idea but the
more he looked at the zoopraxiscope, the more inefficient he found it to be. He
especially disliked that it depended on images obtained with multiple cameras,
feeling it would be more practical and cost-effective if one camera could
record successive images of a body in motion. Thus was born his next quest, or
as some suggest, the next quest for his assistant, WKL Dickson. Doubts remain to
this day how much Edison actually put into it, and how much Dickson did.
No matter who had the ideas, Edison was determined that
Edison Labs take credit. Anxious to protect his invention-in-progress, he filed
a caveat at the Patent Office in October, 1888, describing his idea for a device
that would “do for the eyes what the phonograph does for the ear".
Edison called it the kinetoscope, taken from the Greek
kineto for movement and scopos for watch. The initial kinetoscope did borrow
from the phonograph, using a cylinder upon which tiny photographic images were
affixed in sequence. When the cylinder war rotated, the illusion of motion
was created, using reflected light. He subsequently discarded this version
on the grounds of impracticality and began to look to the ideas of others
engaged in the same quest.
French physiologist Étienne-Jules Marey had his
chronophotographe which used a continuous roll of film to project still images.
Edison found the film to be of insufficient length and durability.
John Corbutt was developing sheets of
emulsion-coated film. When the Eastman Company produced their own version of
the film, Edison bought up large quantities.
In 1890, Dickson and
another assistant, William Heise, came up with an improved kinetoscope that
advanced a strip of film using a horizontal feed mechanism. On May 21, 1891
they demonstrated a prototype Kinetoscope that used 18mm wide film and
functioned as both a camera and a viewer. When used as a camera, a rapidly
moving shutter exposed the film at an intermittent rate; when used as a viewer the spectator
looked through the same aperture and saw rapid intermittent views of the
positive print. As explained at the outset of this post, when frames are
presented at such a rapid rate, the mind sees them as being in motion.
On August 24 of that year, the Edison Company filed a patent
for a Kinetoscope using 35mm film. When completed in 1892, the Kinetoscope
consisted of wooden cabinet, standing 4 feet tall, with a peep hole and
magnified lens at the top.
Inside, a fifty foot
length of film with sprocket holes punched along each side, wound in a
continuous loop around a series of spools, advanced by an electrically-driven sprocket wheel at a steady rate.
Beneath the film, a
rotating shutter with a narrow slit opened and closed in rapid succession to
admit a brief flash of light from an electric lamp under the film. So brief
was the flash of light that the frame appeared to be frozen. However, the frames
passed so quickly that the observer peeping through the lens saw a jerky but moving
picture.
A later version kinetoscope used a vertical feed, and it was
this model that was used in the first public debut, a demonstration that took
place on May 9, 1893 at The Brooklyn Institute of Arts and Sciences.
Two
inventors, C. Francis Jenkins and Thomas Armat invented a film projector called
the Vitascope and asked Edison to supply the films and manufacture the
projector under his name. True to
Edison’s penchant for putting his own stamp on his work, he declined and
soon afterward, the Edison Company developed its own projector, calling it the
Projectoscope.
On April 23, 1896, in New York City the first motion
pictures to be shown in a "movie theater" drew a capacity crowd. And
with it, the door to inexpensive entertainment opened. Theater was no longer reserved for the rich.
Over a century later we can say the IP camera owes its basic concepts
to Muybridge and Edison. For a moving tour of this evolution check out our video.
If you are interested in purchasing an IP camera or
learning about IP camera systems, visit our website, www.kintronics.com
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