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donr Posts: 14	Posted - Tue Jul 22, 2003 11:19 am  Hi, I want to record, for a video shoot, the audio in multitrack on CEP 2.0, and thought that I would be recording SMPTE on a track as I was laying down the audio on adjacent tracks. The SMPTE would also be going to the camera. However, I have been told that "time stamping" of the multitrack is the correct way to go, because it is a time-of-day signature for the multitrack session as well as for the camera. The scene picks up whatever the current time is...... Does CEP allow this? That the saved session can then be sync'ed to the corresponding video in a post mixing session?
Pro_Support Posts: 85	Posted - Tue Jul 22, 2003 1:59 pm  My knowledge in this area starts to get hazy, but as far as I know, no - CEP does not do this. (although I'd like to be proved wrong!) _________________ -Pro Support Adobe Systems Inc.
MusicConductor Location: USA Posts: 1524	Posted - Tue Jul 22, 2003 2:15 pm  My CEP computer is down right now, but doesn't it support IEC extensions that are compatible with broadcast wave? If so, then it does do this, so long as clocking etc are taken care of properly.
Craig Jackman Location: Canada Posts: 909	Posted - Wed Jul 23, 2003 6:21 am  A couple of months ago Support was playing with Broadcast Wave support within CEP, but I don't think anything came of it ... too limited in it's appeal perhaps? _________________ Craig Jackman Production Supervisor CHEZ/CKBY/CIOX/CJET/CIWW Ottawa, Ontario, Canada
MusicConductor Location: USA Posts: 1524	Posted - Wed Jul 23, 2003 9:26 am  That's the question. Broadcast wave and the EBU extensions already supported in 2.1 are pretty close to the same thing, if I'm not mistaken. Anybody use CEP to edit files on a Tascam MX-2424? That would settle it (in a positive way) right there. With Adobe's launching of CEP/Audition as part of a video "suite" it would seem like this would be a mandatory feature. You've seen the publicity, right?
SteveG Location: United Kingdom Posts: 6695	Posted - Wed Jul 23, 2003 11:15 am  donr wrote: Hi, I want to record, for a video shoot, the audio in multitrack on CEP 2.0, and thought that I would be recording SMPTE on a track as I was laying down the audio on adjacent tracks. The SMPTE would also be going to the camera. However, I have been told that "time stamping" of the multitrack is the correct way to go, because it is a time-of-day signature for the multitrack session as well as for the camera. The scene picks up whatever the current time is...... Does CEP allow this? That the saved session can then be sync'ed to the corresponding video in a post mixing session? If I've understood this correctly, you are going to run into some difficulties with using CEP as a master sound recorder synced with a camera at the same time, because you are not going to have a situation where you can get the SMPTE data synchronously to the two machines involved with them both in record mode. Your real difficulty is going to be to get the time-stamped data to record synchronously with the audio, I think. Your camera may well be able to record the two together, and in this case what might work (although I have no idea whether it really will) would be to record a long enough track on CEP, and output the CEP MTC into a converter and thence feed it to the camera. So CEP is in multitrack record mode, but it has to be the Master Sync Source (playing back the pre-recorded track). Now if that all works, (if!), then you would be recording the CEP timecode to the camera. Now this all presupposes a whole raft of things, especially about your camera, which may not be true. And I've never run CEP like this either, so I'm guessing a bit, even about CEP. But at least by explaining this much, you'll get an idea of what you're up against. Basically, CEP2.x can support a MTC (SMPTE) clock, either as Master or Slave, via the MIDI sockets. But how you utilise this is, to say the least, not straightforward in this situation. _________________
MusicConductor Location: USA Posts: 1524	Posted - Wed Jul 23, 2003 1:07 pm  ...which, if it can run in a slave mode, makes it possible that the camera or another source could be the master, right? The way that CEP stays sample-locked is that not only must it be fed MTC, but also a master word sync clock that is also reading or generating the same SMPTE/MTC data. The key to this whole thing, if I'm not mistaken, is to have a "timepiece" stitch it all together. Ultimately, such a device could serve as the master and feed all the ancillary equipment what is needed to stay locked. Or am I on the wrong planet for lunch?
SteveG Location: United Kingdom Posts: 6695	Posted - Wed Jul 23, 2003 4:06 pm  MusicConductor wrote: ...which, if it can run in a slave mode, makes it possible that the camera or another source could be the master, right? The way that CEP stays sample-locked is that not only must it be fed MTC, but also a master word sync clock that is also reading or generating the same SMPTE/MTC data. The key to this whole thing, if I'm not mistaken, is to have a "timepiece" stitch it all together. Ultimately, such a device could serve as the master and feed all the ancillary equipment what is needed to stay locked. Or am I on the wrong planet for lunch? This is convoluted, and difficult. No, you're not on the wrong planet... but in order to run in slave mode, there has to already be a track to slave to - and the real problem is probably that it requires MTC, not bog-standard LTC or VITC timecode that a camera might provide. So even if you could start with TOD code from a master unit, it wouldn't get recorded in that format by CEP - even if CEP would record timecode - which it can't. All CEP could possibly do is chase-lock to an external source that was converted from SMPTE T/C in one form or another, or provide an output of MTC from the internally playing source. For CEP to record-lock to external TC would require the input soundcard clock to be genlocked to TC as well, otherwise the transitions would all end up in the wrong places. It works with analog tape (after a fashion), because you are actually laying down a signal on the tape, and you just record this as it arrives. If CEP would record MIDI, then there would be a potential work-around, because the MIDI data would be shoved into frame alignment anyway, which would be more than accurate enough for film use. But even if you tried the same thing with CEP that you did with analog tape - ie, recording the LTC as audio, you'd be stuck, because there is no way to synchronise an incoming code stream to anything but the MTC clock stream generated by the S/W - and if you replayed the audio LTC into an LTC-MTC converter and tried to lock to this, you'd have a race hazard, because you'd be trying to lock to yourself, only delayed slightly... so it can't possibly work. I have to say that what donr is asking is a pretty tall order for any system, unless it's specifically resigned to do this - like the old capstan-locked multitrack recorders were/are. I presume that the newer multitrack HD recorders will do something like this, but I haven't actually checked their capabilities in this area, because I'm not working in post-prod sound at present (I used to, and I'm quite pleased not to be at the moment!). And talking of things that I haven't read in detail... I will go and read what Adobe have said about what they're proposing for Audition - but I'm pretty sure that it will relate to a playback-based post-production environment, because that's where the rest of their S/W is in this area. After all, for most film and video work, you just need to record the live sound and then add everything else in post anyway - so your synching requirement never normally arises at recording time - when quite frankly, you've usually got enough on your plate without worrying about multi-track sound as well! _________________
donr Posts: 14	Posted - Wed Jul 23, 2003 11:35 pm  Hi, I thank all respondents for a lively discussion. My aim has been to record, to a laptop, all the following sources at the same time: boom mic 2 wireless lavs an ORTF stereo pair for room tone and let the Post House sort it all out. I would send the monitor mix to the camera for reference, Sync the laptop to the camera, and record each day's scenes as CEP sessions on the internal hard drive. Export them to an external Firewire drive. Master clock needs to be this time-of-day SMPTE that runs 24 hours straight, and feeds camera, recorder, and the slate board.
SteveG Location: United Kingdom Posts: 6695	Posted - Thu Jul 24, 2003 6:54 am  donr wrote: My aim has been to record, to a laptop, all the following sources at the same time: boom mic 2 wireless lavs an ORTF stereo pair for room tone and let the Post House sort it all out. Well that bit won't be a problem as long as you have a firewire multi-input device to get it into the laptop - nothing else will keep all those inputs separated out onto individual tracks... Quote: I would send the monitor mix to the camera for reference, Sync the laptop to the camera, and record each day's scenes as CEP sessions on the internal hard drive. Export them to an external Firewire drive. Master clock needs to be this time-of-day SMPTE that runs 24 hours straight, and feeds camera, recorder, and the slate board. I just don't think you can do this, I'm afraid. I'd love to be proved wrong, but somehow I don't think that I will be - reasons in previous post. You need a recording app that is multi-input capable, and capable of recording the master clock at the same time. And then have the ability to lock this clock to an external reference. Are there any apps that record MIDI and audio at the same time? One of those might do as a recording app, and with a bit of juggling, you might be able to rearrange the tracks so that CEP has them in the right place - but this is still going to require a lot of mucking about, I think. _________________
Poco Location: USA Posts: 2	Posted - Thu Jul 24, 2003 8:17 am  I am an MX-2424 (Tascam 24 track HD recorder) user and I have a similar question. The Braodcast wav file that the MX downloads has a timestamp embedded. However, when I edit a file downloaded from MX with CE2000 then upload it to the MX (download and upload via the MX software), the positioning data is gone. This is a real pain in the butt, as the MX has a lot of professional features (like "load to original position") that make it easy to manipulate recordings but that also rely on the timestamp data. Does anyone know if there is a setting in CE2000 that avoids screwing up the timestamp data? Thanks, Poco
MusicConductor Location: USA Posts: 1524	Posted - Thu Jul 24, 2003 9:15 am  Hi again Poco -- you found the "other" thread! I took a stab at this with your other post at 'MX-2424 Timestamp' where I said that CE2000 won't do this but CEP2.1 will. Please see the other post for a few more details.
MusicConductor Location: USA Posts: 1524	Posted - Thu Jul 24, 2003 9:20 am  SteveG wrote: ... but in order to run in slave mode, there has to already be a track to slave to - and the real problem is probably that it requires MTC... Thank you for the clarifications, Steve. That's starting to make sense. I've never actually gotten this to work and haven't yet the hardware to do so (long, long overdue). All I knew was that the computer hardware needed both MTC and work clock. Now the rest of the dubious picture is becoming clearer. I don't recall any detail in Adobe's publicity pertaining to this, and I hope you'll prove me wrong. This issue involves a very odd marriage of hardware, software, and standards -- and no department seems to want to own up to the task!
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