Page 4 - Cinerama_booklet

ca" perceive would be concentrated in one area, he could turn the
principle of peripheral vision to practical film-making advantage.
The shape of the Cinerama screen is Waller's solution to that
problem. It covers an arc of 146 ° -approximately the same as the
human eye, and curved to conform to normal perception of depth. A
curving screen, however, poses special problems. To keep the image
uniformly clear at every point, Waller placed on his projectors special
lenses of great focal depth. To prevent light from bouncing back and
forth from one side of the screen to the other and distorting the image,
he devised a revolutionary louvred screen. Although it looks solid from
a distance, the Cinerama screen is in fact made up of hundreds-

eleven hundred, to be precise-vertical strips of perforated tape,
angled like the slats of a Venetian blind that has been set on end.
Reflected light bounces off one louvre to the back of the next, which
in turn deflects it harmlessly to the rear. Waller's standard Cinerama
screen measures 75 feet from tip to tip, and 26 feet high.
To fill this screen adequately involved almost fifteen years of
constant research on Waller's part. Today's Cinerama camera is in
fact three cameras in one. Through three separate 27 mm lenses-
approximately the lens of your own eye-it takes three pictures simul-
taneously on three separate rolls of film. Set at 48° angles to each
other, each lens covers precisely one-third of the entire picture, the
one on the right photographing the left third, the one on the left
photographing the right third, and the one in the center shooting
straight ahead. A single rotating shutter assures simultaneous expo-
sures on each of the films. Single focus and diaphragm controls adjust
the settings on all three lenses at the same time.
In the theatre, of course, the process is simply reversed. The pro-

jectors, grounded in concrete, are locked together by motors that auto-
matically keep the three images in perfect synchronization on the
screen. Perhaps Waller's most ingenious invention is his device for
obscuring the join lines where the three separate images meet upon
the screen. Tiny comblike bits of steel are fitted into each projector
at the side of the film gate. Jiggling up and down along the edges of
the film at high speed, they fuzz the edges of the pictures and minimize
the lines between them. The first projectionists promptly dubbed them
"jiggolos"-and the name has stuck .

• The oversized reels which feed fil m

the Cinerama projectors hold 7 ,500 fe
of f ilm which runs up to 50 min u e