Jacek Zagaja

Aaton XTR sync start/stop

52 posts in this topic

6 minutes ago, davidm said:

The "Aaton code" is the same SMPTE/EBU timecode format that is used in audio files of the currently available professional audio recorders. If you have the technology to read the Aaton code from the film - a telecine with the Aaton timecode Keylink hardware reader and the Keylink / Indaw software, you can sync audio with matching timecode to the film.  Alternatively, you could output the video though the Keylink hardware reader and software and then sync the audio in and Avid, FCP or Resolve. 

+90-10+20+80.... 

 

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Keylink is no go. I asked my lab and response was null. Why I can't do this manually?

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Keylink is no go. I asked my lab and response was null. Why I can't do this manually?

If you want to do it manually, why bother with TC? Just do it manually.

Maybe if your question didn't change all the time, and you simply explained in some detail what it is you are trying to do, people here would be better able to help you

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Constantin, I want point and shot and not bother with sound at all - like a camcorder. First we discussed trigger coupled with camera button but there is no solution we must hack remotes for popular recorders. Second solution is timecode exposed on film and in audio file but I am amateur and don't know how to handle in popular apps that why looking for advices. If I could have time code displayed with audio file then could copy fragment that is on film and combine. Is there any other solution without pushing rec or slate button each scene?

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OK. So now that we understand what you are trying to achieve we may be able to help better. I think you might need to talk to your lab and telecine. See if they can produce a telecinied video with BITC, burnt in Timecode, which is what we used to do a lot of back in the day. This burns in the value of the TC on the film (which presumably was jammed to Time of Day when shooting) and burns that value onto the bottom of the picture from the telecine. You can now use the TC values from your audio tracks to line up sections of audio to sections of picture. In the 80s and 90s this was done at the labs, overnight, and thus synced up rushes were produced by the next day.

The labs would also produce a 'flex file', which had lots of columns of different TC values on it. In short, one set of values was for the negative roll number TC values (often started at roll 01:00:00:00), and the other column would have ToD Tc values for the in and out points for the audio. With these flex files it would be possible to make an edl in the edit (using negative roll number TC values) and translate these values to sound roll TC values, so that the right sounds could be put in the right places on the timeline, matching sound and pictures.

It sounds complicated, but it used to happen all the time, and when it worked it worked very well, When it went wrong it was a major timewaster.

Good luck, Simon B

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Aaton Code is on the edge of the film outside the scanned picture area. There is no way to use this timecode without the Aaton Code hardware reader on the telecine machine. If the telecine has the reader then as Bash notes above, you can have that timecode burnt into the vision.

Without the Aaton code reader on the telecine, the only practical way to sync the film with audio is with a slate, either plain clapsticks or a timecode slate. 

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David, I have no problem requesting to scan whole are of film. See attached scan of Ektachrome 400. ASCII code is K452 from XTR.

AatonCode.jpg

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the problem is that what you see here is the manufacturer key code, it has no reference to what time the footage has been exposed, so you can't use it for time code.

with film, what you would need is a machine that exposes the timecode on the film while shooting (usually the camera), then another machine which uses this optical information back into computer readable numbers (the key code system on the telecine).

if you're missing either of those components then there's no way to have things synched automatically. so try to find a lab that still has a machine that can read your systems timecode (aaton or arri).

and shoot a test, since these things often don't work (or are handled improperly)

chris

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It is key code because I did not have OriginC to initialize TC. I thought I can extract TC from audio file and see in let say Premiere.

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1 hour ago, Jacek Zagaja said:

It is key code because I did not have OriginC to initialize TC.

well, you could probably use the key code of the film to help, but you still need a way to expose a TC stamp in camera, and a system in telecine to read and translate that stamp back to numbers.

1 hour ago, Jacek Zagaja said:

I thought I can extract TC from audio file and see in let say Premiere.

well, TC on audio is no problem.

I experimented with synch audio on 16mm cameras a while back. the best way I could find without TC reader on telecine or clapperbord was: 

- attach a light portable decoder to the 16mm camera, on one track record scratch audio (either on camera mic or wireless hop from mixer), on the other I attached a contact mic to the camera motor, so that i got a nice loud rattle with minimal ambient sound.
- then sync the on-camera-recorder audio with production audio using plural eyes.
- the put it into a timeline and examine the contact mic track for waveform, and align the flash frame from the telecine footage with the rattle waveform parts. I've found that i get about 3-4 frames offset because it needs a fraction of a second for the camera to get to sync speed, but the offset was fairly consistent.

you could so a similar workflow and record AUDIO-TC from a Tentacle or other box to one of the on-camera-recorder tracks, sync that with the production audio (on davinci or Avid etc), and use the rattle waveform for visual sync again.

or you could even send the contact mic wireless to the mixer and record the motor rattle directly on a track there, this way you could skip the step of aligning the two audio files.

hope that gives some ideas

chris 

 

 

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Nagra 4.2 can be started/stopped shorting Mixer pins - will test soon.

But my newly purchased 4.2 has T12 only (no selector). How can I connect P48 mic or dynamic?

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1 hour ago, Jacek Zagaja said:

But my newly purchased 4.2 has T12 only (no selector). How can I connect P48 mic or dynamic?

do a google search, it will have something

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Have al;ook at Ambient and see if they make an Eumel to do this. ;-)

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well, buy an old T-powered mic then? won't cost you much more then a converter.

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Yes Google explains opposite connection only.

It's true, these things are difficult to find. Eumels are certainly not the answer. Most supply 12T from 48V, but not the other way around. You could use an external box to supply the 48V, but I don't know how that box will like the 12T coming out of your Nagra.

Or have someone custom make a solution for you, it can't be that difficult.

 

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Maybe internally. Someone here with better knowledge of the 4.2 can better answer that

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And advice how use LN (low noise) vs. STD tape selector. Crystal sync works, QLSI is there.

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Jacek Zagaja - A bit strange T12 cannot be switched off.

Constantine - Maybe internally. Someone here with better knowledge of the 4.2 can better answer that.

Jacek Zagaja - And advice how to use LN (low noise) vs. STD tape selector...

When it was introduced circa 1970, the Nagra IV featured modular microphone preamps. They were typically two small circuit boards mounted to a ceramic (if I recall correctly) connector that mated to the mother board of the recorder. The unit was a bit smaller than a pack of cigarettes. One could open the top deck of the recorder and swap out the boards to configure the recorder as needed. Several microphone preamps were available but the two most common were the QPM 200 XOYO and the QPM 3-5. The 200 was used with standard 200-Ohm microphones and the QPM 3-5 supplied 12-volt Tonander power for use with Schoeps and Sennheiser microphones like the MKH 804 and, subsequently, the MKH 805, 815, etc.

This configuration carried over into the new model as the Nagra IV-L was replaced with the model 4.2, circa 1971. The newer recorder was about 98% the same but incorporated a more robust top deck and head mount configuration. It was less susceptible to having heads knocked out of alignment by banging around on location. There were also some slight changes in bias alignment protocols.

Some years later - I don't recall exactly when but certainly by the early 80's - the modular microphone preamps were replaced by universal preamps with switchable powering. Obviously that was a more desirable feature but one did lose the multi-position low frequency rolloff that was a feature of the QPM-3-5 preamp.

It was theoretically possible to tune the recorder to use two different tapes with different bias settings. I think the idea was that one might use low noise tape in critical recording situations and ordinary bias tape for archival or anthropologic recordings. I don't think that plan worked out well in practice. Getting an optimal tune when setting bias is a complex process of boosting one adjustment screw while monitoring an oscilloscope and/or noise tracking monitor and then going back and resetting all the other adjustment screws that were slightly altered in the process. Several passes through all the settings were required to get everything optimal. While I never tried it, I suspect that trying to make two adjustment settings that one could switch between was probably self-defeating. In any event, I don't know anyone who tried it; everyone just set up the recorder to work optimally with a designated tape and ordered a supply of that medium. In practice, the machine was just operated with the switch in the LN position.

BTW- The bias setting was optimized for a particular tape speed. The machine was either tuned for 7.5-ips or for 15-ips. (Or theoretically for 3.75-ips) One could switch between speeds at will but the best frequency response would only be achieved at the chosen bias speed.

David

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Thanks for explanation David. So I'm looking for universal mic pre, plexi cover, rubber gasket.

Is there external crystal sync (record and playback) for Nagra SN?

Purpose of red cover?

IMG_6072.JPG

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Jack Zagaja - ...so, I'm looking for universal mic pre...

Well, not exactly. The universal preamps didn't just mount onto the motherboard in the way that the QPM series of modular boards had. There was a configuration screw on the outside frame that permitted making changes without opening the top deck of the recorder. So, in addition to mounting a different internal preamp, there was also a mechanical link. With suitable parts it probably wouldn't be difficult to make the change-over but it would, at least, require the services of a technician.

The red cover is an RF shield for the playback head. With the use of timecode, the timecode signal was so strong that it would bleed into the playback head and corrupt any attempt at replaying a take. The flip-up shield protected the head from that spurious signal. It was also useful in other situations - the Nagra had always been vulnerable to strong external signals on playback. One sometimes had to literally walk the recorder off set to check playback if there were strong electromagnetic signals in the area. Playback while working on an insert car was often a challenge because of the proximity of the on-board generator.

David

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How connect 816T mic to Nagra 4.2? Plug/socket has different diameter, Nagra has modern XLR socket. Mic comes with MZA15 battery adapter and MZF15 highpass filter.

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The 816T was usually fitted with a male 3-pin  Tuchel connector. The Tuchel connector is essentially a DIN connector with a locking collar.

Some microphones of that period were converted to XLR connector and, later, Sennheiser began to offer microphones fitted with XLR connectors at the factory. Factory-fitted XLR connections were within the manufacturing run of the 816T.

So, you'll need a cable that directly connects the microphone fitting (3-pin, either Tuchel or XLR) to the 3-pin XLR of the Nagra. It should be a simple straight-thru connector with no battery pack or powering devices. The Nagra (if fitted with the appropriate pre-amp as discussed above) will provide T-power directly.

Although no longer in common use, Tuchel connectors are easily available. Amphenol has the license to make them in the U.S. and they should still be available from the larger parts suppliers. They're not so readily stocked as before but I found this example on Ebay:

http://www.ebay.com/itm/Connector-plug-DIN-3-pin-female-locking-screw-type-Tuchel-3-pin-/302189763797?hash=item465be9dcd5:g:hd0AAOSwo4pYcKqL

David

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Ok disassembled Tuchel and cable has signal wire plus shell. Do you remember pinout in Nagra? 1 is ground and 2,3 is signal. I should short 1+3?

IMG_6122.JPG

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