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Posted by Winbert Hutahaean (Member # 58) on August 16, 2009, 11:23 PM:
 
I don't have a Pedro Box but from the previous thread here, I got some idea how Pedro box works. By using Pedro therefore:

1. We need a separate box for PAL and NTSC films

2. We have to precisely start the DVD at the exact frame with the 8mm

3. We are not recommended to do reel changeover very often

4. We require to use a fit GS 2100 machine

5. Only GS 1200 can work with Pedro

6. It is best to do for re-recording/re-dub the soundtrack (not for a live sync)

Now, I have also collected some issues that become constraints in using Pedro:

A. Not everybody owns the most high end machine, GS1200
B. (some people) When receive originally in multiple reels, don't want to put in bigger reel because of many reasons
C. When we have the films in different languages, we feel guilty (sorry) to re-dub it with soundtrack coming from dvd (say, the film is originally in English then to be re-dub to Italian. Meaning the English version will be totally removed)
D. Cannot be used for Digest/Edited version

However, after finding another invention in sound reproduction (which is totally not related with 8mm), I got some idea that with this invention we can still produce stereo sound for our 8mm films without a Pedro box.

It starts when I wrote this thread and especially focus on a new turntable with time code vinyl.

You can click this to see time code-vinyl.

Briefly and basically, there is no music on time code vinyl but only a sound of pulse code which is sent to computer (it does sound like fax tone). Then computer will read that code to be correspondent with the data (sound format/MP3). So wherever the DJ is slowing down or forwarding/backwarding the vinyl, it will quickly change the sound in the computer to follow it.

Now what we need is at least a projector with stereo sound capability and the film with a balance stripe.

Step No 1, we record the time code sound (from the time code vinyl) to the balance strip. We don't need to give a cue when recording the time code sound, just start record at any place on the balance stripe. The computer will create the cue later on.

Step No. 2, we reformat the DVD source (which has the same cut/edit) to MP3 format and then link with scratch live box.

Step No. 3, the sound from track 2 of the projector is linked with this scratch live box and we give a cue where the first frame at the projector should be correspondent with the MP3. This cue will be saved in the computer for next show.

With this method therefore:

I have also another idea of using this method for a digest/edited version. But I will explain later on.
Now, I need your input, will that method works? What do you think? Your comment please....
regards
 
Posted by Joerg Niggemann (Member # 611) on August 17, 2009, 01:21 PM:
 
Winbert, here are my thoughts:

In my opinion, the main problem is that both the projector and the timecode source record have to run crystal-locked when recording the timecode signal onto the sound stripe. Otherwise, you won't get a real time reference on your print and the soundtrack won't stay in sync at all.

I'm not sure that the 8mm sound stripe will reproduce the Timecode Signal in an accurate way. Dropouts could lead to glitches in the timecode-readout which will cause the sound to "jump", too. Did you run a test yet?

In fact the idea of synchronizing the soundtrack by timecode signals is worth thinking of, but again first there is the need of a projector which is capable of running as slave of a crystal-locked reference signal.

Joerg
 
Posted by Flavio Stabile (Member # 357) on August 17, 2009, 02:59 PM:
 
Winbert,

I'm not sure what you mean when you say

5. Only GS 1200 can work with Pedro

infact Wolfgang Peter Thuille (the creator of the 'Pedro' sync box) produced different variations of his boxes and so the GS 1200 is not the only projector that can work with a sync box.

For example the BAUER T502/T510/T525/T610, with an adaptor, can work with a sync box too...

http://www.super8sync.com/English/P1008Q.html

Even when you say

1. We need a separate box for PAL and NTSC films

this is not completely true.

Wolfgang provides also a sync box, the P1008-GS pro, (instead of the standard P1008-GS crystal) which is suitable for both PAL and NTSC signals.

Personally I use the P1008-GS crystal with my GS-1200 and I re-recorded dozens of features with excellent results. I'm very happy with it and I prefer re-recording single reels (even 400ft) instead of greater ones. I don't use directly the DVD, but I prefer to ripple the video on my PC, and with a sw player/editor I start and execute the sync process.

Never encountered a problem so far... [Smile]

Flavio
 
Posted by Winbert Hutahaean (Member # 58) on August 17, 2009, 08:40 PM:
 
quote:

I'm not sure that the 8mm sound stripe will reproduce the Timecode Signal in an accurate way. Dropouts could lead to glitches in the timecode-readout which will cause the sound to "jump", too. Did you run a test yet?
Joerg, honestly, I haven't run any test. The Scratch Live Box + Serato software is about $600 and I don't have that muchmoney.

But from many readings, I got infos that to read the time-code vinyl can use any needle, even a worst one. So if we transfer the time code to balance stripe, as long as it can produce a good sound, I think it will work

quote:
In my opinion, the main problem is that both the projector and the timecode source record have to run crystal-locked when recording the timecode signal onto the sound stripe. Otherwise, you won't get a real time reference on your print and the soundtrack won't stay in sync at all.
If you see that test done by DJ on youtube, there is no need to run crystal-locked because the needle can be placed at anywhere and the software will find (in mili second) where the right place to start. I can imagine that the time code (in laymen wordings) like a bunch of numbers from 1 to millions. So the beginning of track is no "1", followed by "2", "3", etc. And the Software also place those numbers on MP3 . So wherever we place (say in code no. 38730) the software will run to find that number on MP3.

So, when we moved those numbers (time code) to balance stripe then we need only to cue the first number (i.e the first frame) and the other numbers will follow.

I think it is roughly similar to the old way when recording films was using perforated reel to reel tape.

quote:
infact Wolfgang Peter Thuille (the creator of the 'Pedro' sync box) produced different variations of his boxes and so the GS 1200 is not the only projector that can work with a sync box.

For example the BAUER T502/T510/T525/T610, with an adaptor, can work with a sync box too...
Flavio, you may be right, but those are still high-end machine. However with Serato and Live Scratch Box, we can use any simple machine as long as it is a sound projector.

About the NTSC vs PAL, you are right, there is now a dual system box. But the box is only used to crystal lock the machine. Here, I am thinking to apply a similar DTS reproduction system in a real cinema (and in fact we can use a real 5.1 DTS as the source)

I need some more inputs, especially from those with computer expertise.

regards,
 
Posted by Patrick McGrath (Member # 1210) on August 17, 2009, 09:11 PM:
 
This sounds very similar to the way I used to run my old 4 track cassette multitrack recorder. I would record a sync-pulse onto one of the four tracks and from it I could sync a drum machine, midi keyboards or any time code reading device.
The portion of an audio cassette that was a track was no larger than the stripe on super 8 I'm sure. And the potential for dropouts, etc, seems like it would be similar as well. I never had a problem with fresh tape.
I honestly don't remember all the steps to get from recorded sync to playback, but I do recall it being fairly easy to get going.
Might be onto something here...
 
Posted by Winbert Hutahaean (Member # 58) on August 18, 2009, 06:15 PM:
 
Hi Patrick,

I think you have a lot of experience in using time code, could you share more please?

ps: I am thinking that since every frame is numbered/time coded then if there are missing frames, the box will accordingly order the computer to find the right sound (of course in mili second). If this thing can happen, there shouldn't be any problem with splices/edit, which this cannot be the case when using Pedro box. Any further comment?
 
Posted by Steven J Kirk (Member # 1135) on August 18, 2009, 08:22 PM:
 
I have been dreaming along these lines too. There are a number of computer-based programs they are promising. I too would like to be able to use a twin-track or stereo machine ( not the GS1200.) The sticking point I see is the balance track on super 8 has to record the signal and I think it has to be 'analogue' in some fashion. Will the magnetic stripe accept a 'fax-machine' type signal?
 
Posted by Winbert Hutahaean (Member # 58) on August 18, 2009, 08:43 PM:
 
Steve, I think your (our) dream will come true

quote:
The sticking point I see is the balance track on super 8 has to record the signal and I think it has to be 'analogue' in some fashion.
If you see the demo show on youtube above, it is exactly an analogue sound recorded on vinyl.

As Patrick say we might be onto something here...

Honestly, we are all not a DJ here, but on the other side of another hobby, there is an invention that can be useful for us.

More comment please, so I hope we can ge something.
 
Posted by Joerg Niggemann (Member # 611) on August 19, 2009, 05:17 PM:
 
Winbert, indeed you will have to lock projector and timecode record to a crystal timebase while recording TC to the film. It is NOT enough to have any timecode information on the soundstripe. What you need in addition is a fixed relation between film frame advance and the "counting reference", which is the timecode signal. In other words: If the timecode signal increases by one second, the film has to advance exactly 25 frames while recording (for use with a Soundtrack that was extracted from a PAL Source).

I agree that once you have recorded a locked TC signal onto the soundstripe, you can think of using a simple projector without sync capability for playback.

Joerg
 
Posted by Winbert Hutahaean (Member # 58) on August 19, 2009, 11:56 PM:
 
Joerg,

Perhaps what you are thinking is the time code method long time before the new time code on DJ era.

If you see my youtube link where DJ use vinyl time code and scratch live box (the box that automatically synch between the Turntable and MP3 sound on the laptop), I feel there is a revolutionary new invention in this matter.

(ps: what is seen on the youtube is basically the DJ is scratching (moving back and forward in very quick) a time-code vinyl and the MP3 is also moving back and forward. The sound result is exactly like scratching on a real vinyl. The DJ doesn't need to lock the speed of TT and MP3, but, scratch live box who is doing that)

More comment please,
 
Posted by Joerg Niggemann (Member # 611) on August 20, 2009, 03:28 AM:
 
Winbert, let me try to explain in another way. With scratch live box, you have 2 audio tracks which have to run in sync: A Vinyl record as master and the audio track as slave. No Problem: the box reads the time signal and takes care that the audio track is played back according to movement and time position information of the vinyl record.

If we come to our 8mm film, we still have 2 Audiotracks to sync and they may run together according to speed changes of the projector, BUT there is NO relation between time signal,film and soundtrack until

- you lock film to 25 or 23,97fps during the record process, depending on the source of your soundtrack.

- you take care that the vinyl record is running locked to exact speed where it counts as a real timebase.

Think about the "cheap" Projector: let's assume it is running at 24 fps exactly and the vinyl record counts one second in one second. Now you record the signal to the stripe. The recorded signal will count one second every 24 frames of the film. During Playback, box and software will advance the soundtrack by one second every 24 frames of the film. If the projector slows down, the soundtrack will slow down, too. Fine. BUT: If you have taken the soundtrack from a PAL DVD, one second soundtrack advance corresponds to 25 frames advance of the original DVD movie. As a result, the soundtrack will always run too fast at 25fps, compared to the projector running at 24fps.

Now record the time signal to the projector running at *crystal locked* 25fps: The signal counts 1 second every 25 frames. Playback with "cheap" projector: Box tells soundtrack to advance 1 second every 25 frames of 8mm film, regardless of film speed being 24, 25, or whatever fps. Soundtrack will stay in sync.

Joerg

[ August 20, 2009, 08:03 AM: Message edited by: Joerg Niggemann ]
 
Posted by Steven J Kirk (Member # 1135) on August 20, 2009, 09:59 AM:
 
Okay, for example, say I have ALIENS on super 8 and a Pal DVD of the same: I first transfer the DVD soundtrack - say two track stereo for example - to a computer format. I want to play the super 8 print with the projector driving a laptop with the soundtrack computer file. I think what Winbert is onto is that DJ programs allow vari-speed playing of a computer file. If that software creates a timecode that can be recorded on the soundstripe and then played back into the laptop to drive the playback of the soundtrack file then we are in business.
 
Posted by Winbert Hutahaean (Member # 58) on August 20, 2009, 07:30 PM:
 
Exactly Steve, that was I am thinking of.

I was still puzzling with Joerg's previous explanation to what is the relation between variable speed and PAL/NTSC, because I was talking synchronizing picture and sound format (MP3).

Perhaps what Joerg was saying is when redubing (re-recording) our 8mm films with a new stereo sound coming from DVD (PAL/NTSC) then "Yes" I uderstand there will be a concern here on fps issues.

But will that fps still be an issue when we are synchronizing 8mm and MP3? I don't think so.

Guys, we are all laymen here. No one is right or wrong. So the more input, the closer we are to our dream. So I need some more thesis or anti-thesis please...

cheers,
 
Posted by Joerg Niggemann (Member # 611) on August 21, 2009, 01:37 AM:
 
I really don't intend to destroy anyone's dreams ;-)

OK if you only think of having a variable speed mp3 sound, you will have to adjust the mp3's speed manually and permanently to stay in sync with your s8 print. The time signal won't help you much in that case because again, sorry ;-) overall speed of film and mp3 is not the same and a reference film speed is missing.

If you intend to achieve a perfect sync without manual interaction, you need a time reference for both sound playback and the projector. Your mp3 extracted from a PAL DVD still has a time reference (speed) of exactly "25fps", although it is only an mp3 audio track. That means if your projector is running at only 24 fps during playback, the mp3 has to be slowed down to "24fps" also by scratch live box software.

If you recorded the time signal to sound stripe at only 24 fps, the box will take that 24 fps or any speed the projector was running at as the reference film speed and will not slow down the mp3 accordingly. Thats why the projector has to run at the same speed as the soundtrack does *once* when recording the time signals. The time recording process then creates the correct reference for film speed, which is missing in your setup.

Joerg
 
Posted by Winbert Hutahaean (Member # 58) on August 21, 2009, 06:51 AM:
 
Hi Joerg, thanks for your explanation. You have a wonderful expereince in this matter. Again thanks.

quote:
If you recorded the time signal to sound stripe at only 24 fps, the box will take that 24 fps or any speed the projector was running at as the reference film speed and will not slow down the mp3 accordingly.
But, Joerg, from what the youtube has shown, it is indeed the scratch live box will slow down the MP3 if the DJ is slowing down the Turntable (using the Turntable pitch adjustment or simply by touching the time-coded vinyl). And the process of slowing down the MP3 is done on real-time (there is no delay at all)

(PS: The scratch live box and time-coded vinyl are the revolutionary invention in DJ industry. So the DJ is just doing what he used to do with the conventional Turntable).

It becomes more interesting now...
 
Posted by Joerg Niggemann (Member # 611) on August 21, 2009, 11:01 AM:
 
Please don't take me wrong Winbert, but let me try one last comment ;-)

Yes, the box will slow down mp3 when Projector slows down. But only related to the speed the projector was running at when recording of time signal was done.

If time signal recording was done at projector speed 24 fps and you play it back again at exactly that speed, the box won't change speed of mp3 playback. I think you can agree with that. Now, since your mp3 soundtrack came from a DVD movie of 25 fps, in fact sound is running too fast in that case, if it is not changed.

If Projector slows down to 23 fps or speeds up to 25fps, Box will slow down/speed up mp3 to "speed" of 24/26 fps. Still too fast and always one frame too fast because film reference speed was fixed at 24 during recording of time signal.

What you do with that is sync mp3 to time signal. But you also have to sync film to time signal once before film with time signal can sync mp3. If you don't do that, sync is only relative because overall speed is wrong.

Last thought about relative sync: What do you think happens if projector runs at only 18 fps when you record time signal? Playback at 24 fps would end up in soundtrack running at "30fps", because time signal and film have been synced to 18 fps reference film speed.

Maybe another member can help to put it in the right words. Very difficult to do in a foreign language, and I think my comments have to end here...

Joerg
 
Posted by Patrick McGrath (Member # 1210) on August 21, 2009, 02:40 PM:
 
It seems to me that if I record an MP3 of a dvd soundtrack the result has no fps reference in it whatsoever. It is a standalone wave file.
 
Posted by Joerg Niggemann (Member # 611) on August 22, 2009, 03:36 AM:
 
Patrick, you are right. The audio file has nothing in it referring to fps. But what do you know about playback speed of that file? You know that it refers to the DVD where it came from, and the movie on that DVD has exactly 25fps for PAL. You need to know that because if you play back the audio file unchanged, your 8mm print has to run at 25fps, too. That's why I talk about "fps" also related to the audio file. 25 fps "speed" of audio file and film print is the overall reference speed you have to consider here. As long as reference film speed is missing because time signal has not been locked to film speed, the setup won't work.

Winbert, please think about the following setup:

You record the time signal to the soundstripe. Projector is running at 24 fps. Now play back the recorded time signal, same projector speed. Will the mp3 speed be changed or does it run at "normal" speed in this case?

--> mp3 speed will be unchanged, because projector and time signal had the same speed during record and playback

Again you record time signal to soundstripe. You use the same print and the same mp3 track. Now your "cheap" projector is running at 25 fps. Playback the film with recorded signal again at 25 fps. Will the mp3 speed be changed?

--> again, mp3 speed will be unchanged, because of same speed during record and playback.

Now if you compare these two cases, you have the same print, the same mp3 at the same unchanged speed, but your projector is running at 24 fps in case1 and 25 fps in case2. Can the sound be in sync at all?

Joerg
 
Posted by Steven J Kirk (Member # 1135) on August 22, 2009, 08:07 PM:
 
The soundtrack derived from a Pal DVD has to be replayed at 96% of its speed. That will be 24fps. The trick is then to get the sound and picture in sync and there has to be a 'manual' element in that only a person can see when it matches, obviously.
 
Posted by Bill Brandenstein (Member # 892) on August 26, 2009, 07:37 PM:
 
Another thing to keep in mind is that extracting the audio to mp3 means that it's no longer 5.1. BUT in theory this software ought to achieve Winbert's dream of preserving sync if correct starting point can be determined, etc.

This can't work with 5.1 because the software would no doubt fix speed problems by resampling on-the-fly. Resampling an AC-3 or DTS stream would destroy the data integrity and would no longer be recognized as 5.1.
 
Posted by Steven J Kirk (Member # 1135) on August 27, 2009, 11:56 AM:
 
Ah ha! That's where the multi-track portastudio comes in handy. These are the 4 or 8 track recorders based on - in earlier years - cassette, or latterly minidisc or memory card as a medium. You could certainly have a DVD derived 5 way soundtrack - personally I'm not worried about the sub-bass - on one of these. £200 for the portastudio, £100 for a mixer. That's still half the price of a GS1200 and we are aiming for 5 way stereo, not two way. I have a pair of nice Elmo ST600s with twin-track and a Eumig 938 stereo so this approach appeals to me. I'm sure this IS technically possible, even with a twin-track machine. It is just a matter of how far one might want to go. One needs an analogue timecode on the balance track that has already been matched to the digital source and then plays the portastudio to match.
 
Posted by Winbert Hutahaean (Member # 58) on August 27, 2009, 02:23 PM:
 
Guys,

We have all been dreaming this thing to be realized....but...

As a thread starter, I have been taking few days to re-thinking again and again what Joerg has told here.

and I should say:

HE IS RIGHT.....!!

It is impossible to do this because the time-code recorded to balance strip will (or is possible to) get constant or sync with the MP3 files, but WILL necessarily NOT with the picture projected by 8mm projector.

It is hard to explain this, but I will present this explanation with picture, next time, to describe why.

But don't worry in the mean time I am still thinking another way that possible to realize our dream.

I previously on the very beginning say
quote:
I have also another idea of using this method for a digest/edited version. But I will explain later on.
And this is possibly another theory to answer our dream.

I hope Joerg will still be involved in this discussion to give anti-thesis if necessary.

cheers,
 


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