Quick question about timecode. at DVinfo.net

Go Back   DV Info Net > The Tools of DV and HD Production > All Things Audio

All Things Audio
Everything Audio, from acquisition to postproduction.


Reply
 
Thread Tools Search this Thread
Old November 30th, 2008, 02:38 PM   #1
Regular Crew
 
Join Date: Oct 2007
Location: Canada
Posts: 141
Quick question about timecode.

Hi guys. Just wondering if anyone would know if you can use a field recorder that has timecode, such as the Sound Devices 702T, with a camera that does not...e.g. the sony EX1.
I want to get a recorder with timecode because I will get a camera with timecode sometime in 2009, but, in the meantime, I want it to be able to work with the camera I already have.

AIGA (All info greatly appreciated). Lol.
Spencer Dickson is offline   Reply With Quote
Old November 30th, 2008, 04:24 PM   #2
Inner Circle
 
Join Date: Mar 2005
Location: Hamilton, Ontario, Canada
Posts: 5,742
Quote:
Originally Posted by Spencer Dickson View Post
Hi guys. Just wondering if anyone would know if you can use a field recorder that has timecode, such as the Sound Devices 702T, with a camera that does not...e.g. the sony EX1.
I want to get a recorder with timecode because I will get a camera with timecode sometime in 2009, but, in the meantime, I want it to be able to work with the camera I already have.

AIGA (All info greatly appreciated). Lol.
Depends on what you mean by "use it." There are a number of timecode workflows possible, some of which do not require the camera to have TC I/O. Remember that TC for digital video has a different purpose than TC in film (where it controls the speed of playback during telecine) and also the application of TC with file-based digital recorders is substantially different from TC with a DAT. With a file-based recorder such as the 702T code is not recorded continuously with the audio - rather, it is used to set a timestamp at the start of file. Position within the file is calculated at playback by adding the number of samples since the start to the starting timestamp. It provides a position reference but not a speed reference. That means the TC serves to align the video and audio at a single point but does not lock their speeds together. Longish scenes that are aligned into sync at the start of the take may be out of sync by the end and TC by itself does nothing to remedy that.

One workflow is to use a "smart slate" at the head of each take that displays timecode and is set ("jammed") by the TC output of the recorder. Another is to send the TC output to an audio track on the camera - some NLEs such as Avid can read the code from the audio track recorded alongside the video and create a secondary timeline from it. But at best all you'll get is perhaps a more convenient way of establishing lineup than you do with an old fashioned clapper slate and the editor's eyeballs. And BTW - a camera with TC I/O doesn't change anything in that regard. To have a speed reference so that the audio files and the video are locked in sync requires they share a common sample clock timebase but TC doesn't do that. That's where such things as genlock, wordclock, video blackburst, etc come into play.
__________________
Good news, Cousins! This week's chocolate ration is 15 grams!
Steve House is offline   Reply With Quote
Old November 30th, 2008, 04:37 PM   #3
Trustee
 
Join Date: Aug 2008
Location: New York
Posts: 1,844
- You could feed the TC from the 702 to a camera audio track. Of course one would need a LTC reader in post. Some Avids can extract LTC from the audio trk. I don't think FCP can do that yet.

- Smart slate. At least the camera would have a visual TC slated reference. (could be used in conjunction with above.)

Personally I would just slate with a non-TC clapper and spend the 1k+usd elsewhere.
Rick Reineke is offline   Reply With Quote
Old November 30th, 2008, 04:49 PM   #4
Regular Crew
 
Join Date: Oct 2007
Location: Canada
Posts: 141
So from what you guys are saying, timecode in and of itself is not a sync-up panacea. Interesting.

I am more than content to line-up the audio to the video by using a slate. I just wanted to know if it was a good idea to buy a recorder with timecode, and if using such a device as the Sound Devices 702t would create hassles when working with non-timecoded video. Does the 702t output all audio with timecode? If so, it shouldn't affect manually syncing the video to the audio by matching the waveforms, right?
Spencer Dickson is offline   Reply With Quote
Old November 30th, 2008, 07:20 PM   #5
Trustee
 
Join Date: Aug 2008
Location: New York
Posts: 1,844
Right. It would affect anything, except your bank account.
Rick Reineke is offline   Reply With Quote
Old November 30th, 2008, 07:24 PM   #6
Regular Crew
 
Join Date: Oct 2007
Location: Canada
Posts: 141
Great! My bank account can handle it...so is it worth it to get as a feature?
Spencer Dickson is offline   Reply With Quote
Old November 30th, 2008, 07:49 PM   #7
Inner Circle
 
Join Date: Sep 2003
Location: Portland, Oregon
Posts: 3,259
I've shot many hours of dual-system video with a 744T and Sony Z1. Because I was not in circumstances that allowed the use of slates, we mostly went with time-of-day timecode.

We'd set both devices for free-run (not record-run) TC, and manually sync them. This process was good for rough sync - to get the right audio take together with the right video take. We probably got better than 15 frames.

From here, it was easy to use waveforms and reducing and eliminating echo between the camera audio and the 744 audio for fine sync.

I can recommend this workflow for long takes (we were covering music events, with 20-minute to 1-hour takes). If your EX1 TC generator works like Sony's tape-based cams, eg. PD-150, PD-170, HVR-Z1, HVR-V1, then it ought to work for you.

So, yes, I think TC capability is a very good thing in a location audio recorder, even if your current camera doesn't support TC Jam & etc.

And of course using your recorder with a smart slate provides usually painless sync in post. But there's nothing wrong with a dumb slate & sync to the clap - it's a proven workflow when you can get in there with a slate.
Seth Bloombaum is offline   Reply With Quote
Old December 1st, 2008, 05:40 AM   #8
Inner Circle
 
Join Date: Mar 2005
Location: Hamilton, Ontario, Canada
Posts: 5,742
Quote:
Originally Posted by Spencer Dickson View Post
So from what you guys are saying, timecode in and of itself is not a sync-up panacea. Interesting.

I am more than content to line-up the audio to the video by using a slate. I just wanted to know if it was a good idea to buy a recorder with timecode, and if using such a device as the Sound Devices 702t would create hassles when working with non-timecoded video. Does the 702t output all audio with timecode? If so, it shouldn't affect manually syncing the video to the audio by matching the waveforms, right?
The 702T does not output ANY timecode with the audio - ever. It has a timecode connection that accepts code from external sources and/or outputs code from the recorder's internal clock during recording and playback but the TC signal is not mixed with the audio signals. Video timecode (VITC) is inserted into the vertical blanking part of the video signal, it's a part of the video data stream. But audio timecode, LTC, is linear and when present is an audio signal on its own channel completely separate from the actual audio beinmg recorded or played. Back in the analog days a half-track tape from a TC capable recorder such as Nagra would have three tracks in it - the two main left and right stereo audio tracks and a narrower track along the edge with the timecode signal. The audio file that is written to disk or flash card and is copied to your computer for editing, etc, does not contain any embedded TC information with the audio date. All it contains is just a single reference timestamp of what the recorder's TC clock was reading when the first sample was captured. Editing and audio software that understands BWF files will see that timestamp and compute the running timecode from it on the fly, those that don't just ignore it and treat the file as a plain vanilla WAV file. So there]s nothing in the audio that would interfere with using it any way you need. The only time the 702T actually outputs linear timecode with the audio is when you use the 702 as your actual playback device and take the signals from the analog audio outputs plus the (also analog) TC output and even then, everything stays isolated in its own channel.
__________________
Good news, Cousins! This week's chocolate ration is 15 grams!
Steve House is offline   Reply With Quote
Old December 1st, 2008, 07:39 PM   #9
Regular Crew
 
Join Date: Oct 2007
Location: Canada
Posts: 141
Oh...okay. That's great to know that it will work for me. You guys are so friggin knowledgeable here. I hope to have enough skills to be able to impart knowledge to others at some point. Haha.

While on the topic of Sound Devices products, I was wondering if anyone knew if the 744t actually has four channels available, or if it only has two main tracks and then two additional channels that have their own preamps attached. The reason is, I plan on having a main mic, and then two or three lavalier mics, depending on the requirements of the scene, and need at least four tracks in a recorder.
Spencer Dickson is offline   Reply With Quote
Old December 1st, 2008, 08:23 PM   #10
Inner Circle
 
Join Date: Sep 2003
Location: Portland, Oregon
Posts: 3,259
Channels 3 & 4 on a 744T are very good channels indeed, but do not have mic preamps. Line-level input on a mini-XLR connector, aka. TA-3F.

Channels 1 & 2 are identical, but for having regular XLR-F inputs with mic preamps that will supply phantom.

The best setup is to pair a 744T with a 442 mixer - that gets you a nice front end for all channels, great management of the mix, etc. Other alternatives would be mics straight into Ch. 1&2, and some mixer into Ch. 3&4 of a 744T.

A 744T & 442 & a smart TC slate and you have the basic building blocks of a truely pro field setup. There are ways to do it for less $, at some loss of quality.

I'm not working full-time in field acquisition, the gear above is too rich for me... but I know where to find it when needed. Most people who aren't going to bill 10+ days a month with this gear would rent rather than purchase.

Last edited by Seth Bloombaum; December 2nd, 2008 at 12:51 AM. Reason: typo
Seth Bloombaum is offline   Reply With Quote
Old December 1st, 2008, 08:38 PM   #11
Trustee
 
Join Date: Aug 2008
Location: New York
Posts: 1,844
Yeah.. I forgot to mention... what Steve House said.. without being so eloquent and educational. Thanks Steve
Rick Reineke is offline   Reply With Quote
Old December 2nd, 2008, 02:50 PM   #12
Major Player
 
Join Date: Aug 2007
Location: Austin, TX
Posts: 383
Quote:
Originally Posted by Seth Bloombaum View Post
A 744T & 442 & a smart TC slate and you have the basic building blocks of a truely pro field setup. There are ways to do it for less $, at some loss of quality.
With the exception of a very few select gigs, most that I work on are done without ANY timecode. Oh, I jam my slate and all my tracks have timecode on them, but nearly every project is done on gear where the camera can't take TC, so they end up hand syncing the audio and video if they opt to use the secondary audio I give them (most end up using the audio fed to them by the camera).

Wayne
__________________
Mics: KMR 82 i, NTG-1, MKH418S, MKH8040, SR77, QTC1, QTC40, SR30
Recorder: Zaxcom Deva 5.8 & MIX-12. Wireless: TRX900 stereo, Lectro 411
Wayne Brissette is offline   Reply With Quote
Old December 2nd, 2008, 03:26 PM   #13
Regular Crew
 
Join Date: Oct 2007
Location: Canada
Posts: 141
Thanks for all the info guys. Most helpful. I can't wait to go broke again! Lol.
Spencer Dickson is offline   Reply With Quote
Old December 10th, 2008, 07:36 AM   #14
Major Player
 
Join Date: Dec 2005
Location: Melbourne, Australia
Posts: 595
Rick - although Final Cut Pro can't read analogue timecode directly, you can use third-party tools:

VideoToolshed
Chris Hocking is offline   Reply With Quote
Old December 10th, 2008, 03:02 PM   #15
Trustee
 
Join Date: Aug 2008
Location: New York
Posts: 1,844
Thanks Chris, I was not aware of VideoToolshed.
Rick Reineke is offline   Reply
Reply

DV Info Net refers all where-to-buy and where-to-rent questions exclusively to these trusted full line dealers and rental houses...

Professional Video
(800) 833-4801
Portland, OR

B&H Photo Video
(866) 521-7381
New York, NY

Z.G.C.
(973) 335-4460
Mountain Lakes, NJ

Abel Cine Tech
(888) 700-4416
N.Y. NY & L.A. CA

Precision Camera
(800) 677-1023
Austin, TX

DV Info Net also encourages you to support local businesses and buy from an authorized dealer in your neighborhood.
  You are here: DV Info Net > The Tools of DV and HD Production > All Things Audio

Thread Tools Search this Thread
Search this Thread:

Advanced Search

 



Google
 

All times are GMT -6. The time now is 09:04 AM.


DV Info Net -- Real Names, Real People, Real Info!
1998-2017 The Digital Video Information Network