Stereo 16mm ??



Is there such as thing as stereo 16mm? "No" is the correct answer.

(From Alan Scott)

Hi Alex, if you inspect the tracks with a magnifier, I bet they are identical.

I have never came across a stereo track printed on 16mm. I may be wrong though. It would be a great experiment if a print had a stereo track & you rigged up 2 photodiods to try to reproduce it.. I have several prints with twin tracks - regrettably all mono.

(From Jay)

The two light impulses you see on a 16mm sound track mean that the sound has been re-recorded. When 35mm is reduced to a 16mm negative, the reduction process causes the sound to lose its distinctness and can make the sound (especially dialogue) sibilant, hissy and flat. Re-recording brings up the fidelity by raising the bass the treble, thereby retaining the original quality. On some 16mm prints you'll actually see half a soundtrack. This was a way to save money on negative costs with resultant poor quality sound. If you see a half soundtrack where a full one should be-----avoid it like the plague.Jay F.

(From Frank)

YOU ARE CORRECT SIR! You DO see two tracks on 16mm.....sometimes even more. However, these are not distinct stereo tracks, but the same mono trackreproduced in duplicate or quadruplicate (I recall the Bell Telephone science series had six "tracks" -- but don't hold me to that, I am tryin to recall when I was running a theatre in my dorm recreation room -- 1977 -- I was 5 at the time). The reason for the use of multiple, identical tracks has to do with geometry. It is to minimize azimuth errors. If the track is not perfectly perpendicular to the scanning slit, i.e., exactly 90 degrees, then distortion will occur proportionate to the degree of error. To minimize this azimuth distortion (it makes "s" sounds sound like sandpaper rubbing on sandpaper), multiple soundtracks are laid down. Remembering our geometry axioms, we will see that the angle of error will be diminished on any one of the individual tracks proportionally to the number of tracks. Or so I have been told. Please don't ask me to do the math. Therefore multiple tracks are laid down to minimize any azimuth error in the scanning slit lens assembly. But, one bright person might ask, if you can fit two optical tracks in the soundtrack area, why not differentiate them instead of making them identical. Make one the left channel and the other the right channel. How rich you would be if you had thought of this before Ray Dolby did. That is precisely what was done. In fact, a number of Eiki and Elmo projectors were outfitted with stereo pickups and were sold as stereo projectors. Personally I have never seen a stereo 16mm print, but that certainly doesn't mean none were made.

I know a projectionist who worked at the Fort Hamilton base in Brooklyn. He insists that when the Army abandoned 35mm for the base theatres, they installed 16mm projectors that could playback stereo prints and they were wired up a Dolby CP50, same processor used for 35mm optical stereo. Since the army always bought their own prints for the base theatres, it is conceivable that they ordered 16mm stereo prints from the studios. After this was not a difficult thing for the studio to provide as they already had the left/right stereo optical track negatives. This was in the late 70s & early 80s, a time when studios still thought nothing of supplying important theatres like Radio City Music Hall with prints made specially for their unique needs. With RCMH, it was less dense prints, timed to allow a brighter picture, given their 90ft screen. Some big flagship theatres even were supplied with an extra "backup" print. The Rivoli in Manhattan always had a backup print sitting in the booth ready to go. The point being, in that climate, they Army, a rather formidable client, could probably ask for the title on 9mm film and they would have gotten it. I specifically asked my friend, don't tell me if the projector had two cells or that they were run through a stereo processor....was the print stereo....DID YOU ACTUALLY HEAR TWO DISTINCT CHANNELS? He said he did. Cars zooming across the screen surrounds are matrixed into the two channels, left & right.

So in THEORY there is no reason why those two optical tracks couldn't be recorded from the same left/right master that is used for the 35mm release print. In REALITY did they ever do it? My friend says yes and I have no reason to doubt him. But then why haven't they shown up in collector's hands if the army was getting them by the truck load. It might be that the army was as efficient in shredding them as the studios, and you can be sure that was one of the stipulations in the army contract. Then again, there may in fact BE stereo prints in the hands of collectors and they just don't know it. After all, how many of you every really checked the tracks for differentiation? Why would you, if you don't have a stereo projector and don't expect there to be any 16mm stereo prints? Well, let's all try it. Let's all start looking at the two tracks on our prints and see if there is stereo left/right differentiation. How to tell? Best way is with a magnifying glass....or a 16mm projection lens used as one. Get a section of the film that has music, usually titling is best. Then just look very carefully and see if the two tracks differ at all. Avoid dialogue because that is recorded pretty much as a mono signal. But music will most always give it away if the tracks are indeed distinct left/right recording. If any army prints did wend their way into collectors' hands surely among all of us here SOMEone will come up with one. It might also be a way of going about finding out would be to call up Eiki or Elmo and asking if the know if any stereo prints were made to play on their stereo machines; after all one would think if they made stereo projectors, they must have know if the industry was going to produce any prints to play on them.

Anyway, its an intriguing question and it deserves a good answer. Let's try to get it. Frank