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Todd-AO How It All Began #4
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This article first appeared in
..in 70mm
The 70mm Newsletter |
| Written
by: Brian O`Brien, Jr., American
Optical Company |
Issue 50
- September 1997 |
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Now back to the film,
and sound. We wanted to have nearly as possible true stereophonic sound.
Now a slight digression for definitions. There are two methods of giving
the observer the sensation of directionality in his perception of a sound
- Stereophonic and Binaural reproduction. The simplest is binaural where
each of the observers ears is
presented with exactly what the ear would receive (in both amplitude and
phase) if he were sitting at the original location (such as in a concert
hall). This is done in practice by recording with two microphones placed
like ears, and then reproducing this into earphones that must be worn by
the listener. On the other hand, with stereophonic reproduction you do
your best to reproduce the complete sound field in the theater that
existed at the original location. This is normally done by multiple
soundtracks and multiple speakers behind the screen and around the
theater. For perfect reproduction an infinite number of both would be
needed, but as a practical matter six sound tracks with three speakers
behind the screen and three sets of surround speakers does an adequate
job. In addition, there is a trick to enhance the sound localization
effect. For a person sitting in the rear of the theater a sound coming
from, say, the left screen speaker will not appear
to be very far off center because of the small angle to the left.
However, if that same sound then comes from the left surround speakers
delayed in phase by a fraction of a second, the impression will be of that
sound increased in amplitude and from way to the left.
Because of this we wanted six soundtracks, three for the screen speakers
and three for the three sets of surround speakers. The problem was that
there was not room on the 65mm film. The solution was to go to 70mm film.
However, it was extremely desirable to be able to run the camera film and
print film on the same sprockets, so the extra 5mm was added outside the
perforations and the soundtracks were placed out there.
Magnetic sound recording had surpassed optical sound in quality, and the
best was using the Minnesota Mining and Manufacturing Company’s (3M Co)
so-called green oxide, which had the ferrite crystal all oriented so the
noise level was much better than with the
liquid applied striping on motion picture film. We initially went
that route but there was one big problem. 3M (of all people!) had trouble
with the adhesive used to laminate it to the film. The sound track would
peel off on the projection room floor. Hence we ended up with liquid
striping for our prints with two sound tracks outside the perforations and
a third track was inside the perforations on each side.
In those days, (and I presume still today) multitrack sound was recorded
on 35mm magnetic film with standard 35mm perforations and this was run at
standard motion picture speed of 96 perforations per second (24 four
perforations frames per second). We used a 5 hole pull down at 30 frames
per second, and so our film moved at 150 perforations per second. Of
course, this is the same ratio as 64 perforations (one foot) to 100
perforations (which we named the “gleep”). Since standard sound
recording equipment was to be used, the editing “sync machines” had to
be built with 65/70mm picture sprocket with a larger diameter than the
sound film sprockets in the ratio of 100/64. We built a series of sync
machines with one picture sprocket and from one to six sound film
sprockets on the same shaft.
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Further in 70mm reading:
Part #4
Film
and Sound
Editing Machines
Editing Accessories
Lenses
The Corn in “Oklahoma!”
Todd-AO
Part #1
Todd-AO Part #2
Todd-AO
Part #3


Internet link:
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Remember that this was
the era when most editing was done on the old Moviola machines. The
Westrex division of the Western Electric Co. had just recently introduced
their new editor that used rotating prisms (glass cube) and continuously
moving film instead of the intermittent sprocket pulldown of the Moviola.
The Westrex machine was far superior, so we had them build them for our
film. They couldn't handle the optics, so we provided the eight sided
rotating prisms. In addition to a magnificent direct view of the film, we
designed them so that the editor could project the image onto a curved
screen so as to be able to better visualize the effect in a theater.
Another modification was to have the sound film run at a different speed
than the picture film i.e., one foot of sound film to one gleep of picture
film so that they would stay in synchronism (the 64/100 ratio).
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All of the editing
accessories, such as reels, hand rewinds, tight winds, of course had to be
made to accommodate both 65mm and 70mm film. The editing reels had to be
made for either 65 or 70, but the rewinds didn’t care and the weighted
roller on the tight winds for spooling film tightly onto core were
machined with a smaller diameter, 65mm wide, portion inside the 70mm lands
and flanges.
Splicers had to be made for the film. We had Bell & Howell build a
treadle splicer for us and we built a few hand splicers.
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I have described the
image characteristics of the wide angle or “Bugeye” lens earlier. The
field of view was 132 degrees wide with the frame capturing 128 degrees.
Because of the distortions described before, the lenses did not have a
single focal length, but rather the
focal length varied depending on the position in the field. Thus we
designated the lenses by their angular coverage rather than the focal
length designation of standard cine lenses.
Mike
Todd in Spain filming "Around the World in 80 Days"
Initially we intended to have only the “Bug Eye” lens, analogous to
Cinerama´s equivalent of only one “lens”. However, the Hollywood
types insisted that they must have a series of “longer focus” lenses
for close-ups etc. We tried to explain to them that they would lose the
audience participation effect if they went to narrower angles, but they
insisted that they would only use them for close-ups. As a result we gave
them 64, 48 and 32 degree lenses in addition to the 128 degree Bugeye. It
was the biggest mistake we ever made!! These great “professional”
cinematographers and directors didn’t have the faintest idea how to use
the wide angle or participation effect, and so in the whole of “Oklahoma!”
the Bugeye lens was used for two shots, the opening scene dollying through
the corn, and one cut from the runaway buckboard carrying Laurie and Jud
to the Claremore party. The
rest was all shot with the narrow angle lenses. Mike [Todd] used the wide
angle a bit more in “Around the World in 80 Days” but not a
great deal more.
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65mm
frames from "Oklahoma!" program.
Some interesting sidelights on the
corn in “Oklahoma!”. In the San Rafael valley south of Tucson,
near the Mexican border where they built Aunt Eller´s house, it was too
cold and dry to grow corn very well. They hired a plant pathologist from
the University of Arizona to try and do it. By starting it early and
watering it daily from a tank truck driven up from Nogales, he was able to
get a small corn field grown near the house. It was so short, that for
shots of Father Carnes coming through the corn field, James Whitmore had
to squat down to make the corn look tall enough! We estimated that the
corn cost about $8.95 per ear. For the 19 second opening shot through the
corn to a panoramic shot they had to inject each stalk of tall corn (corn
never had been transplanted before), put it in a pot, and truck it up to
the top of the hill to make a corn field just for that shot. The shots of
Curly riding past corn singing “Oh What A Beautiful Morning” were all taken
in the valley down near Tucson at some farmers stand of tall Mexican June
corn. Finally they got corn “as high as an elephant’s eye”.
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