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Old February 15th, 2007, 08:01 AM   #121
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Quote:
Originally Posted by Jon Fairhurst
According to Mark Schubin of The Schubin Report, 24fps was standardized due to the need for stable sound, but we owe the specific frame rate to a researcher from Western Electric who measured average hand crank speed at various theaters.

Here's the direct link to his podcast. The 24p story starts at 6:07 which is at about the 40% point.
To second this, there's a similar reference in Scott Eyman's Book "The speed of sound"
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Old February 15th, 2007, 04:35 PM   #122
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Quote:
Originally Posted by Jon Fairhurst
According to Mark Schubin of The Schubin Report, 24fps was standardized due to the need for stable sound, but we owe the specific frame rate to a researcher from Western Electric who measured average hand crank speed at various theaters.

Here's the direct link to his podcast. The 24p story starts at 6:07 which is at about the 40% point.
Quote:
Originally Posted by Dylan Pank
To second this, there's a similar reference in Scott Eyman's Book "The speed of sound"
The references listed in the previous two posts and also cited above, oversimplify the Film Industry's move in 1927 to 24 fps... kind'a like 24 fps for dummies.

Below is a clarification of my previous post. Paul Wheeler says it best in his book, High Definition and 24p Cinematography, Focal Press, 2003, reprinted 2004, 2005. In his book on pages 23 and 24, he states the following:

"...so the SMPTE were on the right track.

The result of this recommendation is that, from the turn of the century to the coming of sound on film, the camera frame rate was set at roughly 16 frames per second. When sound recorded optically in synchronization with the picture came in 1927, the frame rate of 16 fps, or 60 feet of film per minute was too slow to make an adequate sound recording using the optical recording techniques available at the time. More film passing the sound head every second was needed to enable higher frequencies to be recorded with less background noise. By now, it was known that the flicker apparent in a film projected at 16 fps, or thereabouts, started to disappear above a projection rate of 20 fps. At 30 fps it seemed to disappear completely even on the most demanding scenes, these usually being those with pronounced highlights, as flicker is more discernible in the brighter areas of a scene.

In America the mains electricity has a frequency of 60 cycles per second (cps); therefore, a standard synchronous electric motor will have a shaft speed of 1440 revolutions per minute. This gives a shaft speed of 24 revolutions per second. The Americans, who after all pioneered the making of the talkies, therefore chose the very convenient rate of 24 fps as being almost totally free of any flicker, producing a linear film speed sufficiently high to enable good sound to be recorded with the picture on the same piece of film and being absurdly simple to drive the projectors at a constant speed from a simple synchronous motor. This frame rate (24 fps) is today the world standard for theatrical motion pictures."

So we owe the Film Industry's move to 24 fps film speed to the advent of talkies and our 60 hz. electrical system which delivered 24 cycles per second (1440 cycles per minute), along with simple synchronous motors in film projectors.

I hope this clears things up a little, Dave.

Last edited by Dave F. Nelson; February 15th, 2007 at 07:42 PM.
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Old February 16th, 2007, 10:21 AM   #123
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Right back at ya, Dave

Scott Eyman, (1999) The Speed of Sound: Hollywood and The Talkie Revolution 1926-1930" John Hopkins University Press Page 112

The speed of the film bearing the sound track had been standardised at 90 feet a minute, 24 frames a second. Although tradition has it that 90 feet a minute was the optimum speed for quality of sound reproduction, the fact of the matter was, that, originally, Earl Sponable and Theodore Case had experimented with a speed of 85 feet per minute, which appears to have worked satisfactorily. As Sponable says "After our affiliation with the [Fox company] this was changed to 90 feet a minute in order to use the controlled motors already worked out and in use on the Vitaphone System"*. The standardization, then, was not made for sound quality, but for maximum profit for Western Electric.

* Western Electric engineer Stanley Watkins averred that 24 frames per second was not part of a capitalist plot, but a purely arbitary decision. "According to strict laboratory conditions, we should have made exhaustive tests and calculations, and six months later come up with the correct answer." he related in 1961. 'what happened was we got together with Warner's Chief projectionist and asked him how fast they ran the [silent] film in theatres. He told is it was eighty to ninety feet in the best first run theatres and in the second run anything from a hundred feet up. After a little thought we settled on ninety feet a minute as a reasonable compromise."
I hope that muddies things up a little...
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Old February 16th, 2007, 01:24 PM   #124
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Quote:
Originally Posted by Dylan Pank
Right back at ya, Dave... I hope that muddies things up a little...
Thanks for the quote. It doesn't muddy things up at all, it adds more clarity to the discussion.

Quote:
As Sponable says "After our affiliation with the [Fox company] this was changed to 90 feet a minute in order to use the controlled motors already worked out and in use on the Vitaphone System."
Western Electric's "controlled motors" were 60hz synchronous motors that ran at 1440 rpms, 24 cyles per second. Western Electric's employee decided to use Western Electric 60hz synchronous "controlled motors" to add profits to Western Electric's bottom line.

As I said,

Quote:
"we owe the Film Industry's move to 24 fps film speed to the advent of talkies and our 60hz. electrical system which delivered 24 cycles per second (1440 cycles per minute), along with simple synchronous motors in film projectors."
And might I add... Western Electric's 60hz synchronous "controlled motor" profits.

I appreciate the quote and the reference. You have been very helpful.

Thanks, Dave.

Last edited by Dave F. Nelson; February 16th, 2007 at 07:03 PM.
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