Welcome, Guest
Username Password: Remember me
  • Page:
  • 1
  • 2

TOPIC: can i sync video and audio via aux timecode in lw?

Re: can i sync video and audio via aux timecode in lw? 4 months, 2 weeks ago #181504

  • kalimerox
  • Pro User
  • OFFLINE
  • Platinum Boarder
  • Posts: 355
  • 4 months, 2 weeks ago
@ hugly for the drift:

I just used the tentacle sync on a zoom f8 and synced with a sony fs7 or a alexa amira the traditional way. so i havent tried yet the aux timecode on my own. my guess would be: as long as the audio has no drift to the video , it should be fine, no matter how "bad" the device is, as the tentacle is a pretty stable source getting recorded directly to it.

Re: can i sync video and audio via aux timecode in lw? 4 months, 2 weeks ago #181551

  • hugly
  • OFFLINE
  • Platinum Boarder
  • Posts: 16457
  • 4 months, 2 weeks ago
Thanks you,

Even if the used T/C generator wouldn't have any drift at all, the timecode signal is not used to sync devices actively, it's just a running clock. The clock generators used in each device as time reference for all timebased functions (e.g. sample rate for audio recording and frame rate for video) may drift. This produces drifting content even with perfect timecode, unless the devices are genlocked which means one clock generator (reference frequency/pulse) for all recording devices, but recording gear which accepts connecting external reference clock generators exists only in the professional market, as far as I know.

www.bhphotovideo.com/explora/video/tips-and-solutions/timecode-versus-sync-how-they-differ-and-why-it-matters

The question is, how precise are clock generators used in consumer/prosumer/professional gear under different termal conditions, nowadays? I have no idea.
It's better to travel well than to arrive...
Last Edit: 4 months, 2 weeks ago by hugly.

Re: can i sync video and audio via aux timecode in lw? 4 months, 2 weeks ago #181561

  • kalimerox
  • Pro User
  • OFFLINE
  • Platinum Boarder
  • Posts: 355
  • 4 months, 2 weeks ago
great read, thanks!

I m guessing: If there is a close to ideal clock generator (a ambient lockit or tentacle sync ) which gets recorded onto the audio track which is recording .wav and the internal camera audio and the internal camera video are in sync, we should get a close to ideal synchronisation between the original clock generator signal and the recorded clock generator signal. of course if the audio drifts to the video or there is a drift when converting from flexible frame rates etc.. then there is a problem.

this is all on the camera side. on the audio recorder side I can jam the timecode once in a while from the same timecode generator to keep in sync and they tend to stay in sync pretty good these days (at least for sound devices, zoom f8, etc..)


As metioned in the article, this could be the only way to get external recorded audio precisely into sync in your NLE without external tools, because NLEs often just allow a precision of one frame, which from an audio perspective is super inaccurate.

Re: can i sync video and audio via aux timecode in lw? 4 months, 2 weeks ago #181574

  • khaver
  • Pro User
  • OFFLINE
  • Platinum Boarder
  • Posts: 3325
  • 4 months, 2 weeks ago
I record my church’s sermon with 2 Canon camcorders with audio also recorded by the soundboard. With the sermons sometimes lasting close to an hour, I’ve never had a problem with drift between the 2 cameras and the soundboard audio. Today’s devices are extremely accurate. I think what’s more important for an efficient workflow with separately recorded sound is having synchronized starting timecode on all video and audio clips. There are utilities that can read the LTC track in an audio file and export a BWF wav file with that important starting time added to the metadata. Lightworks can read the timecode from BWF files allowing easy syncing with video with matching timecode.
Work Comp: Retired!
Home Comp: Newer! Bigger! Faster!
Send me a tip: paypal.me/4khaver

Re: can i sync video and audio via aux timecode in lw? 4 months, 2 weeks ago #181576

  • hugly
  • OFFLINE
  • Platinum Boarder
  • Posts: 16457
  • 4 months, 2 weeks ago
Thanks for that information, much appreciated.

Can you point to some, possibly free, utilities which can read LTC from audio track and create BWF?
It's better to travel well than to arrive...

Re: can i sync video and audio via aux timecode in lw? 4 months, 2 weeks ago #181577

  • hugly
  • OFFLINE
  • Platinum Boarder
  • Posts: 16457
  • 4 months, 2 weeks ago
One additional point, in case LTC is an audio track of the camera, does anybody know any free software that can read LTC track and generate a compliant format with T/C track which is supported by Ligthworks?
It's better to travel well than to arrive...

Re: can i sync video and audio via aux timecode in lw? 4 months, 2 weeks ago #181578

  • khaver
  • Pro User
  • OFFLINE
  • Platinum Boarder
  • Posts: 3325
  • 4 months, 2 weeks ago
Work Comp: Retired!
Home Comp: Newer! Bigger! Faster!
Send me a tip: paypal.me/4khaver
Last Edit: 4 months, 2 weeks ago by khaver.

Re: can i sync video and audio via aux timecode in lw? 4 months, 2 weeks ago #181587

  • lghtwrks
  • OFFLINE
  • Platinum Boarder
  • Posts: 2927
  • 4 months, 2 weeks ago

Re: can i sync video and audio via aux timecode in lw? 4 months, 2 weeks ago #181591

  • hugly
  • OFFLINE
  • Platinum Boarder
  • Posts: 16457
  • 4 months, 2 weeks ago
Hi,

Thank you for the demo. Unfortunately I don't understand some essential things.

The demo shows matching sequence TC compared with something played in Reaper, as far as I can understand. I would have thought that, at least today, the only way to match sequence TC is manual entry of start TC. Was the different earlier?

Was Lightworks capable of decoding and using LTC recorded on audio tracks of a camera recorded video imported as one clip into Lightworks (which doesn't contain any other TC than this). If so, how was Lightworks told that this specific audio track is to be decoded and used as timecode and not sound?
Was Lightworks at any time able to identify, show and use auxiliary TC tracks, as Media composer does?
What version of Lightworks does the demo show?

Edit: Khaver, thank you for the link!
It's better to travel well than to arrive...
Last Edit: 4 months, 2 weeks ago by hugly.
  • Page:
  • 1
  • 2
Time to create page: 0.30 seconds
Scroll To Top