Elmo ST-1200HD Double System Sync and repair manuals

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jessh
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Elmo ST-1200HD Double System Sync and repair manuals

Post by jessh » Tue May 21, 2002 4:17 am

I was just looking at the manual for my projector and I noticed that it mentions an R-1 synchronizer sync pulse jack. It goes on to say that "The R-1 synchronizer is used to synchronize the Elmo SR-1 Cassette Recorder with the ST-1200HD projector for transferring sync-sound to magnetically striped film. The SR-1 Cassette Recorder when attached to Elmo cameras: 110R 612R or 1018R, utilizes a pulse-sync system for recording sound in post-sync for later sound transfer to the film during projection."

Well it sure sounds to me like the projector will either run at the speed provided by a stream of sync pulses or that it will output sync pulses. Does anyone have any information on this? I would think it is a standard 1khz pulse signal, just because that is what most things I have seen use. Does anyone have any information on these cameras?

Does anyone have a repair manual or anything for this projector? would be nice to have plus might shed some light on the matter.

~Jess

supa_ate_sixteen
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Post by supa_ate_sixteen » Tue May 21, 2002 4:48 am

Hey there,

I got the same projector, ain't it cool?! Anyways, the R-1 sync jack works with sync sound recorders like the Super8Sound recorder. Basically, the recorder uses the pulse information coming FROM the projector and then regulates its speed to the projector. In other words the projector is the "master" and the recorder is the "slave" as they say in sync slang. I am anticipating my Super 8 Sound recorder from Moviestuff any day now so I can test out its sync capabilities with the ST-1200 HD projector. I'm sure you could workout something with a different type of recorder if you are so mechanically inclined. I can barely load a fullcoat recorder let alone modify it for sync sound use. Talk to Roger (Moviestuff), he's the Magyver of Super 8 and can make a sync recorder out of a lightbulb and a watermelon! ;) Good Luck!

jessh
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Post by jessh » Tue May 21, 2002 5:32 am

That is prity much what I figured. any idea if it is 1khz pulses or a roughly 60hz wave?
While a sync recorder made out of a lightbulb and a watermellon is tempting I am leaning more towards doing it in a computer.

Thanks for the info! I would love to ehar how it works out for you.

~Jess

Pedro
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Post by Pedro » Tue May 21, 2002 11:55 pm

The output of the projector is the same thing as a flash contact of a camera. It has a reed contact, that closes once a frame.
This master frequency feeds any pulse synchronizer with 1:1 input, or f.e. the Gebuhr MultiSyn CD-player with in-built synchronizer. For computer freaks, this way you can make your soundtrack on PC, burn a CD an control the playback speed of the CD with the projector.
For normal tape use, you need a compatible tape recorder. The motor regulation circuit must be electronically be influenced by the synchronizer, feeded by the projector. And the tape recorder must report it´s own actual speed, f.e. by outputting a sequence of 1000 Hz pulses to the synchronizer. The basic thing is, that the tape player must be compatible to the synchronizer and there unfortunatly never had been any industrie standard for that. So, unfortunatly, an apple and a watermelon is not enough. In the 1970ies there had been a kinda "war" between the different sync system supplyers, and each of them had created different, not compatible systems, yes they even scratched away the lables of the integrated circuits!
I am also working on synchronizin electronically the differnt devices. Basically you can afford a regulation for any unknown tape player of motor viewer, when the baby has a pitch control regulator.
You bypass the pitch control, using a batch of 5 potentiometers of the same value, connecting each of them into the original circuit, using an opto coupler for each of them. each optocoupler you drive with one of the 5 digital outputs of my synchronizer P1008. The synchronizer now activates the potentiometer no. 3 when audio and film only differ 1-2 frames (neutral posiion). Potentiometer 2 is driven, when the audio is 3-4 frames behind the film, potentiometer 4 is driven when the audio is 3-4 frames ahead to the film. Potentiometer 1 and 5 are driven, when the diference overrides +/- 5 frames. Now you set poti 3 in a way, that the baby runs at normal speed, poti 2 in a way, that the audio runs about 1-2 fps faster and poti 1 for the audio running about 5 fps faster than normal. Accordingly adjust poti 4 and 5.
Now you have determined the regulation characteristics of the system and the synchronizer will choose automatically one of that speed settings or toggle between the speed settings in order to create intermediate steps. And the system will run frame accurate in sync, at any time.
BUT: you need a device specific interface!
Pedro

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Post by supa_ate_sixteen » Wed May 22, 2002 4:04 am

I've read a little about the Gebuhr MultiSyn CD-player with in-built synchronizer and was wondering if they work well with the Elmo ST-1200 HD? All you need is a CD burner and the CD- player unit to work with the projector for complete sync capabilities? How does your method record your initial pulses? I've heard you talk a lot about perfo tape, which we use more traditionally as fullcoat. They both serve the same purpose. I have a Super 8 Sound recorder that has built in synchronizer and works with fullcoat. Thier latest model out, the Mark IV. Would I just transfer this soundtrack along with the pulse track to my computer and then burn that information onto CD? How much is the Gebuhr MultiSyn CD-player with in-built synchronizer?

Whats a pointometer again?

Pedro
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Post by Pedro » Wed May 22, 2002 2:33 pm

The MultiSyn CD player works with any projector that has a reed contact. And you can apply a reed contact to any projector, even crank driven.
To produce a soundtrack, you really only need a PC or MAC with CD recorder. However, you must have your edited film transfered to a digital format, that you can load into your video edtior. Then you add your soundtracks, aligning them to the now visible frames. Live sound you must squeeze and stretch until it matches more or less. After having produced a stereo mix out of your sound track, you export it to wav. Then you take a virgin CDR and record as a first track the Gebuhr init track from the included CD. As a second track you record your wav file.
Then you load your film into the projector and forward it to the marked start frame. Start the CD-player, it will play the short intit track and this way setting all parameters. Then it will stop automatically. Now you start the projector as ususal, and the CD player will follow up automatically, always keeping the sound in sync.

Perfo tape and full coat is very similar. The big difference is sound quality. Perfo tape is standard studio tape, thin and smooth, running with high speed, while full coat is thick, providing a bad head contact and running only at original film speed. Sync coupling is made only electronically when using perfo tape, it is traced by an opto coupler - no sprockets.
For sound track production, you can edit everything on perfo tape, using a multitrack reel-to-reel tape recorder with optocoupler for perfo counting. Each counting unit showed by the counter corresponds exactly with one frame of your sound story board. The perfo frequency can be used to control the sound transfer from a field sound recorder, using a synchronizer. After finishing, you hook your tape recorder to the synchronizer and switch it to crystal mode. Now the perfo tape is running perfectly with crystal framerate, as like any digital audio media. Easy job to mix and sample the sound to hard disc and to produce a cd.
The advantage of perfo is, that you can include your field sound easyer and without any stretching, when working without crystal camera. And many people like direct intuitive analouge mixing with big sliders more than mouse clicking.

A potentiometer is a variable resistor, like a regualor.

Pedro

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Post by supa_ate_sixteen » Thu May 23, 2002 8:28 pm

Ok Pedro I understand, mostly.

So here is a situation then I'm wondering if I'm understanding correctly.

So I shoot my film double system with a non crystal camera and a Sony DAT which is crystal.

I then transfer my film to digital and my sound and line up everything in my NLE.

Now your saying if I were to magically cut the original print to my master video tape (which would be pretty darn hard to get frame accurate) then I can just take that soundtrack from the NLE and burn it with the CD-player unit and it will regulate the film print to perfectly synchronous lip sync sound?

It seems there might be issues with everything lining up correctly. I mean, there is still a 1:1 relationship with the video to film but I don't see how it works out. Does the CD-player unit regulate the projector almost like a crystal sync unit? Or does the projector control the speed of the sound?

How much in US dollars is this nifty little CD-player?

Guest

Post by Guest » Fri May 24, 2002 12:20 am

The easyest way is to FIRST finishing your film (silent) and THEN transfer it to digital.

When you the see your film like a row of frames in your video editor, you align all synchon and not synchron sound, music etc to separate tracks.
sync sound you must squeeze/stretch in order to align the first and last frame of the szene and perform a test run in the NLE system of this scenes.
Then you mix everything to stereo, export it to wav and burn it on CD.
During projection, the projector will slightly change the speed of the CD in order to match it´s own difference to crystal. These regulations are so gentle, that nobody can recognize it.

When you wish to FIRST edit even the film in NLE and cut the master film afterwards frame-accurat, you NEED a transfer with frame numbers. Here in Germany we have the service for PAL transfers with superimposed frame numbers. During the transfer, a second video camera is capturing a digital frame counter and superimposing that into the resulting picture.
Now you can cut your NLE video however you want, you always keep the frame number of your original film. When finished, you run your film thru a viewer with single frame counter, f.e. the Beaulieu "master cut", with locked sprocket driven counter. and separate your film in singular scenes, according to the video result. You pin each scene on a board, right in the order you have cutted it from the original reel, giving it the number of the scene according to the video. Now you splice everything together, in the order of the scene index numbers, until you have used all material that was pinned up, and your film will match exactly to the video, and the sound also.

Pedro

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paul
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Post by paul » Fri May 24, 2002 12:32 am

ok, supa ate sixteen, I will answer part of your question. The cd player Pedro is talking about is 970 euro Vat included. That will be 850 USD. It is Manufactured in Germany.

Paul

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