8mm Forum: Silent Film Instability at Sound Speed

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Topic: Silent Film Instability at Sound Speed

Brad Kimball
Phenomenal Film Handler

Posts: 1171
From: Highland Mills, NY USA
Registered: Jun 2003

posted July 27, 2018 09:44 PM

Whenever I run a silent print at 24fps on any of my projectors the picture is never free of being shaky yet at 18fps it’s perfect. Why would a silent print with no mag striping be so unstable. I could see if ine edge of the prints had more weight (like a sound print minus a balance stripe). Doesn’t seem to matter which print(s) or which projector. Odd that with 16mm I don’t get the same effect. Only with Super 8 Silent prints.

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Panayotis A. Carayannis
Jedi Master Film Handler

Posts: 969
From: Athens,Greece
Registered: Jul 2008

posted July 28, 2018 03:07 AM

Are,perhaps,your silents (or,some of them) old and dry copies that need lubrication? And, because the tension at 18 fps is lesser than at 24 they run ok at 18. My guess.

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Steve Klare
Film Guy

Posts: 7016
From: Long Island, NY, USA
Registered: Jun 2003

posted July 28, 2018 03:07 AM

-a wild guess:

The only difference I can think of is the stripe.

There has to be a little slop between the perfs and the claw. That means there can also be a little vertical bounce too. Maybe at 24 FPS there's enough added energy in each pulldown that it tends to rattle around before it settles down.

With the stripe in there there's a little added friction and it resists this: kind of like a tiny set of brakes.

16mm doesn't have the stripe, so it has to be immune to this through other means.

I would guess a machine with side pressers in the gate would handle this better than one without.

I usually do 18 FPS with silents: I'll have to give this a shot and see what happens!

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All I ask is a wide screen and a projector to light her by...

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Adrian Winchester
Film God

Posts: 2941
From: Croydon, London, UK
Registered: Aug 2004

posted July 28, 2018 10:48 PM

I was going to offer the same theory as Panayotis, as I've sometimes reduced speed to get a seriously unsteady reel through a projector, to avoid unthreading it.

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Adrian Winchester

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Brad Kimball
Phenomenal Film Handler

Posts: 1171
From: Highland Mills, NY USA
Registered: Jun 2003

posted July 28, 2018 11:40 PM

I could see where with a few prints if lubrication of the film was needed it could help, but I must have about 40 different silent prints. Yet with a dry print with striping on it I don’t get any issues. I rarely lubricate film for fear that too much chemical applied over time could be more of a detriment than a benefit. I think I’ve only used my FilmRenew a dozen or so times over a ten year period and only on prints that were utterly disgusting when won on an auction site.

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