8mm Forum: Standard (Regular) 8mm sound movies...

This is topic Standard (Regular) 8mm sound movies... in forum 8mm Forum at 8mm Forum.

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Posted by Flavio Stabile (Member # 357) on December 18, 2014, 12:26 PM:

So far i knewthe the sound is recorded, on regular 8mm films, 56 frames (I also read 54 frames) in advance with respect to the image.
The EUMIG dual format projectors let the 8mm to have a longer path before the film pass trhough the sound head.
I noticed that instead the BAUER T 192 and SILMA DELTA 4 (both dual format) doesn't have this characterics.
The result is that the sound is out of synch with imagees...

Why? Is the "56 frames" not a standard?

Posted by Mal Brake (Member # 14) on December 18, 2014, 01:48 PM:

From what I recall, (and I stand to be corrected) standard 8 was derived from 16mm but with twice the number of sprocket holes giving twice the number of frames per length of film.
16nn optical sound film has a picture / sound separation of 28 frames, so standard 8 mag sound kept the same pic/sound equation but with twice as many frames per any given length of film, so
28 X 2 = 56. The arrival of super 8 changed matters.

Posted by Flavio Stabile (Member # 357) on December 18, 2014, 02:03 PM:

This is an interesting and really reasona le explanation... But it doesn't answer why projectors of different brands manage in different ways the same move format....
Why do Bauer and Silma maintain for 8mm the same film path of Super 8, giving origin to out of synch movies?

Posted by Maurice Leakey (Member # 916) on December 18, 2014, 02:33 PM:

Mal's explanation of standard 8 magnetic sound separation is quite correct.

Posted by Thomas Dafnides (Member # 1851) on December 18, 2014, 08:42 PM:

The Bauer/Silma brand dual 8 projectors (1980's) were designed for those who wanted the ability to record their own soundtracks on standard 8mm not playback pre-packaged films. Obviously, they felt the demand to play standard 8mm sound film in the 80's had dwindled , so that it was not worth the extra cost to design/manufacture a projector with a flexible sound/picture separation path as in the earlier Eumig models.
By the 1980s, the mass market for super 8 was in rapid decline. Manufacturers wanted to cut costs.

Posted by Paul Adsett (Member # 25) on December 18, 2014, 08:53 PM:

Still, it's very hard to believe that Bauer & Silma in the 1980's deliberately departed from the (then) 25 year old standard of 56 frames sound separation for standard 8. Eumig did their dual 8 projectors the right way, and in a very clever manner.

Posted by Maurice Leakey (Member # 916) on December 19, 2014, 02:43 AM:

I have a Duo Sound 225 Electronic (made by Silma) which is a dual gauge projector which has the change between gauges by the simple sliding of one control.
Various guides move around below the gate to guide standard 8 films into a larger loop to maintain the standard 8 separation.
I attach a link to its brother, the Exakta Elektronic 450 SEL Duoplay.
http://www.super8data.com/database/projectors_list/projectors_exakta/exakta_480sel.htm

Posted by Flavio Stabile (Member # 357) on December 25, 2014, 03:27 PM:

Thanks for the replies!
I couldn't imagine that for 8mm, to guarantee the standard of correctly reproducing pre-recorded sound movies could be a choice for the projector manufacturer... But this is the reality, of course!

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