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optical audio on 16mm film

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Anonymous
September 18, 2004 5:24:27 AM

Archived from groups: rec.audio.pro (More info?)

i've been setting up the sound for the st louis afana screenings for a
few years (http://www.afana.org/), and have taken an interest in the
sound system of 16mm films -- when i look at the optical audio track
on 16mm film, it kinda looks like a running waveform, almost what
you'd see on a scope. i only erally thought about this the other day,
and it seems that the easiest way to get audio on film would be a
system that essentially drives a lamp with an audio lamp -- but it
seems this would result in a linear track of varying degrees of grey,
not a waveform display . . .

so, the questions is, what system was/is used to expose the audio
track on 16mm (or any optical audio track) film?


(i'm hoping dorsey will be able to answer this since i know he's
kinduva film buff)


cheers,
chris deckard
saint louis mo
Anonymous
September 18, 2004 11:47:38 AM

Archived from groups: rec.audio.pro (More info?)

mr c deckard <chrisdec@swbell.net> wrote:
>i've been setting up the sound for the st louis afana screenings for a
>few years (http://www.afana.org/), and have taken an interest in the
>sound system of 16mm films -- when i look at the optical audio track
>on 16mm film, it kinda looks like a running waveform, almost what
>you'd see on a scope.

This is called a "variable area" track. It is normally made with a device
called a "light valve" which is sort of like a ribbon mike operating in
reverse. Light is shone between the two ribbons and as they attract and
repel, the band of light between them gets wider and narrower.

>i only erally thought about this the other day,
>and it seems that the easiest way to get audio on film would be a
>system that essentially drives a lamp with an audio lamp -- but it
>seems this would result in a linear track of varying degrees of grey,
>not a waveform display . . .

This produces a "variable density" track. The lamp trick you describe
is called the "Case AEO Light" and was invented by Theodore Case in th
1920s. The problem with the light is that most fluorescent and neon lamps
don't have very good linearity; they tend to want to be either on or off,
and getting a wide range of brightness is difficult.

It is also possible to do variable density tracks with a galvonometer,
which is sort of like a meter movement with a mirror attached to it.
As the meter moves, the reflected light off of it gets brighter and
dimmer.

Variable density tracks tend to be noisy, because any piece of grit on
the track is definitely on the track, whereas with a variable area track,
grit on the black sections is not noticed. Also, there are serious problems
with processing consistency; you need to get a perfect and linear grey scale
on the print for the sound to be good. Variable density tracks are not
popular any more because of the print consistency requirements and noise
issues.

>so, the questions is, what system was/is used to expose the audio
>track on 16mm (or any optical audio track) film?

16mm is almost all variable-area, but you will occasionally find variable
density tracks made on Auricon sound-on-film cameras. The Auricon was mostly
used for TV news applications and would record sound on the same strip of
film the picture was being shot on, for direct video transfer rather than
printing and it was designed more to be rugged than to sound good.

>(i'm hoping dorsey will be able to answer this since i know he's
>kinduva film buff)

If you come to Boston in Feburary for the Arisia science fiction convention,
you can watch I, Robot with a 35mm variable area track, White Zombie (Bela
Lugosi, 1932) in 35mm with a (pretty awful) variable area track, and some
short subjects recorded in 1928 on the Western Electric sound-on-disc system.
We will be showing the latter with synchronized sound on DAT since we don't
have the equipment to play those 16" transcription discs in synch, and
UCLA's archive wouldn't let us borrow them anyway.

If you are really curious, ask your library for _Sound Recording_ by Frayne
and Wolfe. This is the standard reference on optical track stuff. It dates
back to the 1930s, but to be honest most of the current films in theatres
today are being shown with tracks recorded on 1930s RCA optical track cameras.

Also, you can ask Optical Sound Chicago for a tour. They aren't all THAT
close to St. Louis, but they are good folks (and are about the only people
who can make 16mm track that sounds decent today).
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."
Anonymous
September 18, 2004 5:36:34 PM

Archived from groups: rec.audio.pro (More info?)

<< 16mm is almost all variable-area, but you will occasionally find variable
density tracks made on Auricon sound-on-film cameras. The Auricon was mostly
used for TV news applications and would record sound on the same strip of
film the picture was being shot on, for direct video transfer rather than
printing and it was designed more to be rugged than to sound good.
>>



And the audio input for these cameras was on a male XLR, since they believed
that news crews weren't smart enough to figure out which end of an XLR cable
went from the mic to the camera. So, with XLR females on both ends, you'll
never get it wrong.


Scott Fraser
Related resources
Anonymous
September 18, 2004 5:36:35 PM

Archived from groups: rec.audio.pro (More info?)

In article <20040918093634.19486.00000790@mb-m22.aol.com> scotfraser@aol.com writes:

> And the audio input for these cameras was on a male XLR, since they believed
> that news crews weren't smart enough to figure out which end of an XLR cable
> went from the mic to the camera. So, with XLR females on both ends, you'll
> never get it wrong.

Nagra 3 recorders were like that too. I just figured it was a Swiss
thing.



--
I'm really Mike Rivers (mrivers@d-and-d.com)
However, until the spam goes away or Hell freezes over,
lots of IP addresses are blocked from this system. If
you e-mail me and it bounces, use your secret decoder ring
and reach me here: double-m-eleven-double-zero at yahoo
Anonymous
September 18, 2004 9:36:31 PM

Archived from groups: rec.audio.pro (More info?)

Most later Auricons used magstriped film, IIRC, I used these back in
the mid-60's at a TV station. We shot on reversal stock with a chain
driven multi tank processor.
Editing was done on a standard hand crank editor with a jury rigged
tape head to hear the sound which was eiither 24 frames ahead or
behind the picture for sync. ( It was a long time ago and i'm getting
old.) To erase audio while editing, we used a magnet.
The projectors in the MCR had both optical and magnetic sound heads
for playback.

On 18 Sep 2004 13:36:34 GMT, scotfraser@aol.com (ScotFraser) wrote:

><< 16mm is almost all variable-area, but you will occasionally find variable
>density tracks made on Auricon sound-on-film cameras. The Auricon was mostly
>used for TV news applications and would record sound on the same strip of
>film the picture was being shot on, for direct video transfer rather than
>printing and it was designed more to be rugged than to sound good.
> >>


>
>And the audio input for these cameras was on a male XLR, since they believed
>that news crews weren't smart enough to figure out which end of an XLR cable
>went from the mic to the camera. So, with XLR females on both ends, you'll
>never get it wrong.
>
>
>Scott Fraser

Mike Cleaver Broadcast Services
Voice-overs, Newscaster, Engineering and Consulting
Vancouver, BC, Canada
radiovoiceone@hotmail.com
Anonymous
September 18, 2004 9:46:55 PM

Archived from groups: rec.audio.pro (More info?)

"Mike Rivers" <mrivers@d-and-d.com> wrote in message
news:znr1095516509k@trad...
>
> In article <20040918093634.19486.00000790@mb-m22.aol.com>
scotfraser@aol.com writes:
>
> > And the audio input for these cameras was on a male XLR, since they
believed
> > that news crews weren't smart enough to figure out which end of an XLR
cable
> > went from the mic to the camera. So, with XLR females on both ends,
you'll
> > never get it wrong.
>
> Nagra 3 recorders were like that too. I just figured it was a Swiss
> thing.

And Marantz portable stereo cassette recorders. One factor is that panel
connectors for XLR male are, usually, smaller than those for female, an
issue in a portable unit.

Peace,
Paul
Anonymous
September 19, 2004 11:48:10 AM

Archived from groups: rec.audio.pro (More info?)

ScotFraser <scotfraser@aol.com> wrote:
><< 16mm is almost all variable-area, but you will occasionally find variable
>density tracks made on Auricon sound-on-film cameras. The Auricon was mostly
>used for TV news applications and would record sound on the same strip of
>film the picture was being shot on, for direct video transfer rather than
>printing and it was designed more to be rugged than to sound good.
> >>


>
>And the audio input for these cameras was on a male XLR, since they believed
>that news crews weren't smart enough to figure out which end of an XLR cable
>went from the mic to the camera. So, with XLR females on both ends, you'll
>never get it wrong.

You _still_ see that on hotel PA systems today. Means you can pay the cable
out in either direction and not worry. Also I bet people don't steal their
cables.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."
Anonymous
September 19, 2004 7:55:20 PM

Archived from groups: rec.audio.pro (More info?)

<< You _still_ see that on hotel PA systems today. Means you can pay the cable
out in either direction and not worry. Also I bet people don't steal their
cables. >>



Also means you can't send somebody to a Radio Shack to pick up another cable
when an unexpected need arises. Then again, we're not talking audio experts
here, so if the need arises, you'll probably just get a shrug of shoulders,
can't be done.

Scott Fraser
Anonymous
September 19, 2004 8:03:43 PM

Archived from groups: rec.audio.pro (More info?)

<< Nagra 3 recorders were like that too. I just figured it was a Swiss
thing. >>



Seems to be an attempt to prevent people from making a mistake that takes all
of 15 seconds to rectify, in exchange for making your equipment incompatible
with the rest of the world. Good idea.

Scott Fraser
Anonymous
September 19, 2004 8:28:42 PM

Archived from groups: rec.audio.pro (More info?)

In article <cijrlq$bep$1@panix2.panix.com> kludge@panix.com writes:

>
> >And the audio input for these cameras was on a male XLR

> You _still_ see that on hotel PA systems today. Means you can pay the cable
> out in either direction and not worry. Also I bet people don't steal their
> cables.

Oh, I'll bet they lose their share of cables. It's just that it's
inconvenient for the thief to use them as is. A thief doesn't think
too hard when he packs something up that isn't his.

Now if you replaced all of your headphone plugs with XLRs and a thief
had to unplug that connector before walking away with your phones, you
might lose fewer sets to theft. But a malicious thief would take then
anyway just to be nasty.



--
I'm really Mike Rivers (mrivers@d-and-d.com)
However, until the spam goes away or Hell freezes over,
lots of IP addresses are blocked from this system. If
you e-mail me and it bounces, use your secret decoder ring
and reach me here: double-m-eleven-double-zero at yahoo
Anonymous
September 24, 2004 3:03:25 PM

Archived from groups: rec.audio.pro (More info?)

Mike Cleaver <voice.1@telus.net> wrote:
>Most later Auricons used magstriped film, IIRC, I used these back in
>the mid-60's at a TV station. We shot on reversal stock with a chain
>driven multi tank processor.

Mag sound was such an incredible advance in sound quality for news folks,
it just wasn't funny. Also, the mag machines were much more reliable. By
the time mag came in, though, a lot of folks started to move to cameras like
the Frezzolini or the CP-16, most of which were based on the Auricon movement
but which were a lot lighter and more convenient.

>Editing was done on a standard hand crank editor with a jury rigged
>tape head to hear the sound which was eiither 24 frames ahead or
>behind the picture for sync. ( It was a long time ago and i'm getting
>old.) To erase audio while editing, we used a magnet.

The high budget way of doing this was with a thing called a Displacement
Dubber. You would run the film through the displacement dubber in reverse,
and it would play back the signal and then record it 26 frame away so that
the picture and sound were directly parallel with one another for editing.
Then, after cutting, you would run it through the machine forward so that
the audio was advanced 26 frames from the pix for projection. This basically
added two generations of loss to the whole process and resulted in poorer
sound, but it was still better than optical track and it was still very
convenient.

>The projectors in the MCR had both optical and magnetic sound heads
>for playback.

Did you use the same film chain for the news film that you did for the
shows that came on film?
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."
Anonymous
September 24, 2004 7:43:16 PM

Archived from groups: rec.audio.pro (More info?)

Hi Scott!

Yes, the same film chain was used for both. We had two RCA projectors
with both mag and optical readers, a slide machine and a Balop machine
going into a multiplexer (bunch of relay controlled mirrors in a box
with directed the light beam from whatever projector you wanted to air
to the film chain camera (this was all b/w by the way).
We had 1 studio camera and the audio still was done live by a booth
announcer (usually me) into an EV666. Later, we did the tracks on an
Ampex 351 which the audio op fired.
The big improvement came in 1969, when we received a 2" Ampex VTR as a
hand me down from the CBC delay centre.
The beast needed a ten second pre-roll to lock up.
We used to cue the VTR operator from the newsdesk with a home made
foot switch made out of a 100" film can with a momentary switch
mounted in it.
VTR intros had to be at least 15 seconds long.
Our "rear screen" at the time was 2 Kodak Carousels mounted behind the
news set with another foot switch to advance the slides!
Ah technology!


On 24 Sep 2004 11:03:25 -0400, kludge@panix.com (Scott Dorsey) wrote:

>Mike Cleaver <voice.1@telus.net> wrote:
>>Most later Auricons used magstriped film, IIRC, I used these back in
>>the mid-60's at a TV station. We shot on reversal stock with a chain
>>driven multi tank processor.
>
>Mag sound was such an incredible advance in sound quality for news folks,
>it just wasn't funny. Also, the mag machines were much more reliable. By
>the time mag came in, though, a lot of folks started to move to cameras like
>the Frezzolini or the CP-16, most of which were based on the Auricon movement
>but which were a lot lighter and more convenient.
>
>>Editing was done on a standard hand crank editor with a jury rigged
>>tape head to hear the sound which was eiither 24 frames ahead or
>>behind the picture for sync. ( It was a long time ago and i'm getting
>>old.) To erase audio while editing, we used a magnet.
>
>The high budget way of doing this was with a thing called a Displacement
>Dubber. You would run the film through the displacement dubber in reverse,
>and it would play back the signal and then record it 26 frame away so that
>the picture and sound were directly parallel with one another for editing.
>Then, after cutting, you would run it through the machine forward so that
>the audio was advanced 26 frames from the pix for projection. This basically
>added two generations of loss to the whole process and resulted in poorer
>sound, but it was still better than optical track and it was still very
>convenient.
>
>>The projectors in the MCR had both optical and magnetic sound heads
>>for playback.
>
>Did you use the same film chain for the news film that you did for the
>shows that came on film?
>--scott

Mike Cleaver Broadcast Services
Voice-overs, Newscaster, Engineering and Consulting
Vancouver, BC, Canada
radiovoiceone@hotmail.com
Anonymous
September 24, 2004 7:43:17 PM

Archived from groups: rec.audio.pro (More info?)

Mike Cleaver wrote:
>
> The big improvement came in 1969, when we received a 2" Ampex VTR as a
> hand me down from the CBC delay centre.
> The beast needed a ten second pre-roll to lock up.

This should bring back some memories <http://www.lionlamb.us/quadpark.html&gt;

;>
Anonymous
September 24, 2004 7:47:49 PM

Archived from groups: rec.audio.pro (More info?)

Oh,! Some folks might want to know what a Balop machine was.
Think of a giant sllide projector.
You mounted your photographs or artwork on the back of a 4" by 4"
piece of glass.
Those fit into a turntable on the machine which held four of them and
also was advanced by a relay.
It was similar to what old time movie houses used to run promos and
ads.
The poor film room guy had to be a four armed paper hanger back then,
loading and cueing the 16mm films, loading the slide trays, the Balop
machine and the VTR.
They finally had to get a full time VTR guy because the thing was so
time demanding, loading reels, cleaning heads, checking tracking, etc.

On 24 Sep 2004 11:03:25 -0400, kludge@panix.com (Scott Dorsey) wrote:

>Mike Cleaver <voice.1@telus.net> wrote:
>>Most later Auricons used magstriped film, IIRC, I used these back in
>>the mid-60's at a TV station. We shot on reversal stock with a chain
>>driven multi tank processor.
>
>Mag sound was such an incredible advance in sound quality for news folks,
>it just wasn't funny. Also, the mag machines were much more reliable. By
>the time mag came in, though, a lot of folks started to move to cameras like
>the Frezzolini or the CP-16, most of which were based on the Auricon movement
>but which were a lot lighter and more convenient.
>
>>Editing was done on a standard hand crank editor with a jury rigged
>>tape head to hear the sound which was eiither 24 frames ahead or
>>behind the picture for sync. ( It was a long time ago and i'm getting
>>old.) To erase audio while editing, we used a magnet.
>
>The high budget way of doing this was with a thing called a Displacement
>Dubber. You would run the film through the displacement dubber in reverse,
>and it would play back the signal and then record it 26 frame away so that
>the picture and sound were directly parallel with one another for editing.
>Then, after cutting, you would run it through the machine forward so that
>the audio was advanced 26 frames from the pix for projection. This basically
>added two generations of loss to the whole process and resulted in poorer
>sound, but it was still better than optical track and it was still very
>convenient.
>
>>The projectors in the MCR had both optical and magnetic sound heads
>>for playback.
>
>Did you use the same film chain for the news film that you did for the
>shows that came on film?
>--scott

Mike Cleaver Broadcast Services
Voice-overs, Newscaster, Engineering and Consulting
Vancouver, BC, Canada
radiovoiceone@hotmail.com
Anonymous
September 27, 2004 1:23:08 AM

Archived from groups: rec.audio.pro (More info?)

"Scott Dorsey" <kludge@panix.com> wrote in message
news:cih78q$i62$1@panix2.panix.com...
> Also, you can ask Optical Sound Chicago for a tour. They aren't all THAT
> close to St. Louis, but they are good folks (and are about the only people
> who can make 16mm track that sounds decent today).

Any idea why?
--
Bob Olhsson Audio Mastery, Nashville TN
Mastering, Audio for Picture, Mix Evaluation and Quality Control
Over 40 years making people sound better than they ever imagined!
615.385.8051 http://www.hyperback.com
Anonymous
September 27, 2004 1:23:09 AM

Archived from groups: rec.audio.pro (More info?)

Bob Olhsson <olh@hyperback.com> wrote:
>"Scott Dorsey" <kludge@panix.com> wrote in message
>news:cih78q$i62$1@panix2.panix.com...
>> Also, you can ask Optical Sound Chicago for a tour. They aren't all THAT
>> close to St. Louis, but they are good folks (and are about the only people
>> who can make 16mm track that sounds decent today).
>
>Any idea why?

Probably because most people doing 16mm optical tracks don't really care,
and there's such a small market for it. Most folks want bandlimited tracks
that sound good on cheap classroom projectors, rather than full-range low
distortion tracks.

16mm these days is mostly an acquisition format, with most stuff shot on
16mm being being release to video or in 35mm blowup. 16mm as a release format
is pretty dead and there aren't many folks bothering to do good blow-downs
or optical tracks in 16mm because there aren't many folks paying for them.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."
!