8mm Forum: Striped 16mm

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Posted by Kevin Faulkner (Member # 6) on February 03, 2007, 12:16 PM:

I bought a copy of Disney's "Tron" on LPP recently and found that it has a mag stripe down both edges of the film.
Its on the outer edges of the film and covers half the optical soundtrack.
Obviously it has no effect on the optical sound but I do question why this was done in the first place.
Could this have been a TV print with a stereo soundtrack?

Kev.

Posted by Dan Lail (Member # 18) on February 03, 2007, 02:35 PM:

I think it may be for a second language. No sure, but something in the recesses of my mind hints of this. I have an opt/mag 16mm projector, so you're welcome to send it on to me. [Big Grin]

Posted by Hugh McCullough (Member # 696) on February 03, 2007, 06:13 PM:

I have seen two mag tracks on quite a few married print 16mm films.
It could be for stereo, but normally it was done to keep the film completely flat in the gate.
A mag stripe on one side naturally makes the film thicker on that side, so one side of the frame is further away from the lens that the other.
Although this distance is very small, it can cause focus problems when projected on large cinema screens.
Placing a mute track on the opposite side solves this problem.
When I worked for a tv station films with mag tracks were run on doublehead projectors. (Unmarried prints)

Posted by Kevin Faulkner (Member # 6) on February 03, 2007, 06:45 PM:

Hugh, why put a mag track on when the optical track is there to start with. Yes like super 8 I can understand the balance stripe being there but why go to all this trouble in the first place unless as Dan says it was for another language.

Kev.

Posted by Steven Sigel (Member # 21) on February 03, 2007, 08:30 PM:

It's for airline use... The mag stripe had a different language on it. I've got a print of "Vertigo" with a spanish mag track, and "Rear Window" with French.

There's no such thing as a 16mm stereo print - mag or optical (there was an experimental stereo 16mm projector that AMC tried out, but no prints were ever struck for it that I am aware of).

Posted by John A. Pommon (Member # 292) on February 03, 2007, 10:10 PM:

quote:
A mag stripe on one side naturally makes the film thicker on that side, so one side of the frame is further away from the lens that the other.

That's right Hugh, a balance stripe equal to the thickness but narrower than the sound-track side is applied along the opposite edge primarily to equalize the effective thickness of the two edges to obtain a unifirm winding. The stripe is sometimes used for the recording of additional sound or control records.

quote:
Hugh, why put a mag track on when the optical track is there to start with. Yes like super 8 I can understand the balance stripe being there but why go to all this trouble in the first place unless as Dan says it was for another language.

Magoptical release prints having both magnetic and photographic optical sound tracks offered some advantage:

Magnetic tracks are less susceptible to dust and dirt distortion & not affected much by scratches. The magnetic stripe's additional height raises the emulsion off the base side of the next convolution of film on the roll reducing picture area frictional damage, emulsion-to-base sticking, etc. Magnetic tracks have higher fidelity sound (greater frequency response and better signal-to-noise ratio).

Optical tracks last the life of the film and cannot be easily damaged through cleaning or other maintenance of the film & no danger of accidentally erasing the track. Fidelity of optical tracks can be degraded by dirt particles and scratches. Changes cannot be made to optical tracks [after it has been printed on the film].

[ February 03, 2007, 11:19 PM: Message edited by: John A. Pommon ]

Posted by Kevin Faulkner (Member # 6) on February 04, 2007, 05:16 AM:

John that all makes sense. Just wish I had a 16mm machine with Mag playback then I could see if anything was indeed recorded on the stripe.

Kev.

Posted by Hugh McCullough (Member # 696) on February 04, 2007, 06:48 AM:

Just a thought, but as the film is a copy of a professional 35mm film it might have the two types of track for another purpose.

In the 1960s, 70s & 80s there was an experiment with both types of track being on some 35mm release prints. I ran a few of theses films.

The idea was that the film played in cinemas that could run 4 track mag sound, then the film was cleaned, and the mag track washed off. The copy was then redistributed to optical, mono, only cinemas, thereby saving money on extra prints.

Also at least one Bond film had both 3 track mag, (no surround), and an optical mono track.

This seemed to have stopped with the mass take up of Dolby optical stereo.

Could this idea have been continued with some 16mm films? Never seen it myself, but why not? There were quite a few 16mm shows doing the rounds.

quote:
There's no such thing as a 16mm stereo print - mag or optical.

Sorry Steven there is. No many I agree, but I had a Baur machine, can not remember the model, that could run mag stereo. I remember running a Russian version of Robin Hood on it, very badly dubbed, but defiantly in stereo.
As for optical stereo, my present machine has a split Dolby optical stereo cell.

Posted by Kevin Faulkner (Member # 6) on February 04, 2007, 08:36 AM:

Seems there is so much more to learn about 16mm and things which went on which probably didn't see the light of day in the end.

Where would all this be now it weren't for the video revolution.

Kev.

Posted by John A. Pommon (Member # 292) on February 04, 2007, 11:53 PM:

quote:
Sorry Steven there is. Not many I agree, but I had a Baur machine, can not remember the model, that could run mag stereo. I remember running a Russian version of Robin Hood on it, very badly dubbed, but defanately in stereo.
As for optical stereo, my present machine has a split Dolby optical stereo cell.

It's not surprising a Bauer stereo magnetic European model exists. [2 track bilateral stereo head or balance stripe as 2nd channel?]
Stereo 16mm magnetic didn't catch on in the US other than perhaps very special application or experimentally . . . . . (unlike stereo super-8mm).
Just the cost of even mono 16MM magnetic audio prints restricted thier popularity.

quote:
John that all makes sense. Just wish I had a 16mm machine with Mag playback then I could see if anything was indeed recorded on the stripe.

Kev, keep your eye on eBay . . . . do a SEARCH for an EIKI SSL-2 or ESL-2. They are a very good magnetic-optical machine. They show up once in a blue moon.

John

[ February 05, 2007, 09:33 AM: Message edited by: John A. Pommon ]

Posted by John Whittle (Member # 22) on February 06, 2007, 06:04 PM:

Back in the 70s when I worked in post production, we made magopt prints for Puerto Rico with the domestic english on the optical and spanish recorded on the mag track. We also did dual language prints for Candian release in eastern Canada with english/french. A balance stripe is an absolute requirement to maintain focus in the gate on 16mm prints. BTW Eastman's first work on the dual-bilateral dual track optical was to provide two languages on a 16mm print. You'd print from two different sound negatives (with the right printer aperture for each) and then the projector would mask one side or the other to play each language. Stereo came later.

John

Posted by Kevin Faulkner (Member # 6) on February 07, 2007, 01:04 AM:

So we did have stereo on 16mm prints?

Kev

Posted by John Whittle (Member # 22) on February 07, 2007, 09:20 AM:

There may have been some experiments for one theatre chain in the US (General Cinema) which was planning a series of 16mm cinemas using Eastman 25 projectors. But there were not any 16mm stereo optical recorders. There were two RCA stereo recorders and the balance were Western Electric/Westrex/Nuopix (all basically the same machine over many years) which used the ribbon light valve. In theory that light valve could be use with 16mm transports.

More likely if any prints were produced they were optical reductions of 35mm optical tracks (which really don't sound all that good due to image fill in, cross mod problems and wrong equlization for the 16mm film speed).

So while I can't say that there aren't any 16mm dual bilateral stereo prints, I'd have a hard time producing an example of a print. Now it's possible that some current release might use the existant 35mm negative optical track, but that's a guess. Most current release 16mm prints are reductions since so few prints are made, it's not worth it to make up the 16mm preprint elements anymore.

John

Posted by Tony Milman (Member # 7) on February 07, 2007, 01:30 PM:

Kev

Bring it over some time- I have a 16mm Mag/Opt. One film I have has the mag stripe and indeed it has a spanish lang. track recorded on it. Actually makes the film a lot better than in English [Big Grin]

Posted by Kevin Faulkner (Member # 6) on February 07, 2007, 03:54 PM:

I will take you up on that Tony. Lets get all this bad weather out of the way first.

Thats all very interesting stuff John. Obviously a lot more went on with 16mm than we really knew about.

Kev.

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