Recording Synchronous Sound with a Silent Movie Camera

Terry Mester · December 19, 2006

I wish to present to you a new improvement to Cinematography for SYNCHRONOUSLY Recording Sound with silent Movie Cameras. I developed a simple method for keeping the Sound Recording synchronized to the Film Reel. The two HTTP Attachments below explain the process in full detail. I developed the technique for 8mm and 16mm Camera users, but it of course applies to 35mm and 65mm Cameras as well. This new method keeps the starts and stops of the Sound Recording synchronized to the Reel of Film through any number of pauses in filming. This method simply uses one Pause Switch to turn both the Tape Recorder and the Movie Camera on and off at the same time. It doesn't replace "frame by frame" timing provided by a Quartz Clock in professional use, but it makes the process of professional editing and viewing dailies a whole lot easier. For Home Movies it's fantastic to be able to record synchronous sound.

Although this method would eliminate the need for the Clapper in synchronizing for professional use, the Clapper should still be used as backup and also to record the Technical Scene Information onto the Film Reel. Since the Sound Recording would be synchronized to only one Camera, and if filming a Scene with more than one Camera, you need to synchronize all the Cameras together. The best idea is to glue two 'two-pole' Pause Switches together which would enable you to keep three Cameras synchronized to the Sound. This would also end the nuisance of having one Camera run out of Film before the other Cameras. Another method you could also use is to briefly flash a Red Light on the Set for just a split second each time the Cameras are turned on after a pause in filming. You would then simply use the Last Frame of Red Light on each Reel of Film to synchronize all the Film Reels together. You could use both methods for extra safety. In either case, your job has just been made easier for both editing and reviewing the whole Reel of Film.

The two Bitmap Files (which are each 3 MegaBytes in size) can be downloaded by clicking the HTTP Links below, or by logging onto the Website www.geocities.com/filmanddigitalinfo.

http://www.geocities.com/filmanddigitalinfo/S8SOUND1.bmp

http://www.geocities.com/filmanddigitalinfo/S8SOUND2.bmp

Terry Mester · December 21, 2006

ADDENDUM

These Bitmap Files can be printed out on your Printer using any Scanner Software Programme like Microsoft "Image Composer" or "Paint" or "LivePix". You can also download a smaller HTML version (which doesn't contain the Schematic Picture) from the Attachment Link below. It contains all the text.

s8sound.html

Terry Mester · December 22, 2006

FULL HTML VERSION

You can download a complete HTML Version of the Information Sheet (including the Schematic Picture) Attached below. I'm afraid that Yahoo Geocities is deficient, and my Website is being limited as regards downloads.

S8SOUND.html

Federico Casal · February 8, 2007

I wish to present to you a new improvement to Cinematography for SYNCHRONOUSLY Recording Sound with silent Movie Cameras. I developed a simple method for keeping the Sound Recording synchronized to the Film Reel. The two HTTP Attachments below explain the process in full detail. I developed the technique for 8mm and 16mm Camera users, but it of course applies to 35mm and 65mm Cameras as well.

Hey... one question... How can the system work for a Krasnogorsk 3 camera, if it doesn't use any electricity...?

Terry Mester · February 8, 2007

Hey... one question... How can the system work for a Krasnogorsk 3 camera, if it doesn't use any electricity...?

Well, I'm afraid it can't help for a crank Camera. That name sounds like a Russian Camera. You're taking a big risk using a non-electric Camera as regards Film Speed. You'll end up with a movie with differing Frame Rates per Second, and it will therefore be impossible to synchronize the Image to the Sound. I don't know the cost of renting a Super16 Camera in your area, but given the cost of shooting with 16mm Film I think it's well worth the cost of renting a modern Camera. I would personally recommend shooting with Super 8mm before using a Regular 16mm crank Camera. If you're going to spend money on 16mm Film, you really want to receive the full-size Super16 Frame.

Dennis Kisilyov · February 9, 2007

ADDENDUM
These Bitmap Files can be printed out on your Printer using any Scanner Software Programme like Microsoft "Image Composer" or "Paint" or "LivePix". You can also download a smaller HTML version (which doesn't contain the Schematic Picture) from the Attachment Link below. It contains all the text.

Umm, I don't get it. How does this replace crystal sync?

This seems like a simultaneous on/off switch for the camera and tape recorder.

Which is not going to stay in sync if the tape recorder and camera are not crystal clocked. If they are crystal already, it makes it moot since a clapper/slate is the zero latency sync.

Versus a switch which with analogue tape can have an up to 100ms lag/latency while either the camera or the tape get up to speed.

Am I missing something?

Thanks.

Joseph Winchester · February 9, 2007

As Dennis says, this only starts and stops the two in sync with each other. This will, however, not KEEP them in sync. The issue is the camera not running at 24 fps exactly throughout the take, but your audio device will. A crystal sync motor regulates the cameras speed so it is exactly 24fps and will stay in exact sync throughout the recording. Then you can line up your audio recording and it will sync nicely.

With your device, they both will start at the same time, but what if at 10sec into the recording the camera suddenly slows slightly to 22fps then back to 24? Your audio has stayed constant, but is now off by several film frames. That's the problem with syncing, not starting and stopping at the same time.

GeorgeSelinsky · February 9, 2007

The one way you can get audio and picture to line up perfectly is if you have what is called an "interlock" system worked out, where each frame that you advance the camera you advance the audio recorder. Doing this with unsprocketed magnetic tape is impossible because there is no easy way to control the exact position of the tape, which is also prone to stretching.

You'd have to use a recorder that uses magnetic sprocketed film (they used to have those back in the old days, before the Nagra and Pilottone - although I don't believe they worked on interlock). That's quite a difficult beast to get out there.

You can sorta get away with shooting sync using non sync gear (even with a spring camera) if you're willing to spend time in a video editing program cutting and stretching/compressing the soundtrack to make up for the sync drift (pitch correction may be necessary). In that case I advise you to use a video camera or other digital device for sound recording since analog tape drifts like crazy. You'll already have a camera that is drifting out of sync, so the audio should be as stable as possible.

Another problem is that most cameras which aren't designed for sound make a ton of noise, the larger the format the louder. Unless you're outdoors and are shooting from a distance, you're going to get camera chatter on your sound track. Some 8mm cameras might be small and quiet enough if you do a quick blimp on them (throw a jacket over them or mush it between two pillows), but it's not fun to shoot like that.

Consider post dubbing your film, see my article here: http://www.geocities.com/gselinsky/nonsync.html

Terry Mester · February 9, 2007

Umm, I don't get it. How does this replace crystal sync?
Which is not going to stay in sync if the tape recorder and camera are not crystal clocked. If they are crystal already, it makes it moot since a clapper/slate is the zero latency sync.

As Dennis says, this only starts and stops the two in sync with each other. This will, however, not KEEP them in sync. The issue is the camera not running at 24 fps exactly throughout the take, but your audio device will. A crystal sync motor regulates the cameras speed so it is exactly 24fps and will stay in exact sync throughout the recording. Then you can line up your audio recording and it will sync nicely.

Guys, I noted above that this method does not replace Crystal (Quartz) Timing. I developed it for Super8mm use. However, in Professional use with Crystal Timing, it would keep the "duration" of the Sound Recording concurrent with the Film Reel. In later viewing, after syncing the Film & Sound with the first Clapper use, Crystal syncing would keep the Sound synced to the Film for the rest of the Reel. At present, when viewing the Film you need to re-sync with the Sound for every Take. :blink:

George,

What year was Crystal (Quartz) Timing introduced? How difficult was it to synchronize the Film and Sound before Crystal Timing? Pre-1975 Movies don't appear to have any syncing problems.

Leo Anthony Vale · February 10, 2007

What year was Crystal (Quartz) Timing introduced? How difficult was it to synchronize the Film and Sound before Crystal Timing? Pre-1975 Movies don't appear to have any syncing problems.

Xtal sync was introduced in the late60s.

Initally studios used 3-phase Selsyn sync interlock motors on the camera and the sound film recorder, first optical then mag film.

Newsreels used single system sound. 35mm optical usually Wall cameras. 16mm Auricons, initially optical, later replaced by mag striped film. Until video portpacks, TV news was mag striped.

16mm DC cameras would have a sync pulse sent to a 1/4" tape recorder via a cable.

With an AC camera, a similar pulse would be taken from the line current and recorded on the 1/4' tape.

Or was this a trick question for George?