HOW TO SYNC PROD SOUND DVD RAMS TO AVID MEDIA - WORKFLOW QUESTION - SD 24P OS9 MERIDIAN
by riskerone
on
Mar 3, 2007 at 12:57:02 am
Having a confusing time setting up this show.
Here are the specs just to set up the base. We are shooting SD with 24p cameras. Cutting in OS9 meridians media composer 11.2.6. The production sound recordist is recording to DVD-ram. We are digitising the media straight from camera masters.
Here is the problem and I've faced this on another show as well and we couldn't solve.
When we want to import audio from the DVD ram's to cut with split tracks the audio is out of sync. NO MATTER WHAT SPEED / SETTING the production sound mixer uses. We ran 4 tests. 48k with pulldown 16bit 29.97 NDF. 48k with pulldown 16bit 30 NDF. 48k 16bit 30 NDF and 48k 16bit 29.97 NDF. And every one of these tests ended up with a drift of sound.
We can fix this problem if we use the audio suite plugin and time compression expansion with a ratio of .999:1 (basically pulling the audio down to 47.952) But this is a huge pain in the ass and we need to cut with split tracks so we can't be having to use this plugin on everything.
If we set on recording at 48k 16bit 29.97 TC (the standard) speed, how can we "Pulldown" the digital files upon import into the avid so they sync up?!!
PLEASE HELP!!!
Anyone have experience with this and have solved it? I know there is a way to do this.
Re: HOW TO SYNC PROD SOUND DVD RAMS TO AVID MEDIA - WORKFLOW QUESTION - SD 24P OS9 MERIDIAN by John Pale on Mar 3, 2007 at 3:57:24 pm
If you are going to be doing a lot of this kind of work, you are going to need to upgrade to a newer system.
The Meridiens were not designed for this sort of thing. The 24p cameras are really shooting 23.98...not like a film camera with true 24. You really need the option of a 23.98 project.
Have you tried importing into iTunes (change the import preferences to AIFF at sample rate of 47.952) ?
Re: HOW TO SYNC PROD SOUND DVD RAMS TO AVID MEDIA - WORKFLOW QUESTION - SD 24P OS9 MERIDIAN by John Pale on Mar 3, 2007 at 4:02:57 pm
Sorry,
Just checked and iTunes does not allow a custom sample rate. Quicktime player does, but you will need to do them one at a time.
You might also be able to import them into the Avid at 48k, then export them at 47.952, then re-import them. Dont know if that version of Avid software will allow you to enter a custom sample rate for export.
Re: HOW TO SYNC PROD SOUND DVD RAMS TO AVID MEDIA - WORKFLOW QUESTION - SD 24P OS9 MERIDIAN by MichaelP on Mar 3, 2007 at 9:53:41 pm
11.8 offered 23.976 on Meridien based systems. If the sound recordists tried recording at 47.952kHz and it did not sync, then you need to convert outside the application and speed up .1%.
Re: HOW TO SYNC PROD SOUND DVD RAMS TO AVID MEDIA - WORKFLOW QUESTION - SD 24P OS9 MERIDIAN by Mike Most on Mar 3, 2007 at 10:10:25 pm
Your first problem is that you don't want to "pull down" the sound. If anything, you want to pull it up. You shot video, not film. In film, the running speed is slowed down during telecine. With video, it isn't changed at all. The only change it's going through is what you're doing to it by using a 24p project, which is running it faster than it was shot - i.e., you're speeding it up. The easiest solution is to go to a software version that has a 23.98 project type. In this case, you want to bring in the sound as is. It should sync just fine, because you're not changing anything from the "real time" speed it was shot at. The key to staying in sync from any double system elements is that they both need to be running at the same speed. In a 23.98 project, everything would be running at "real time," exactly as it was recorded. Nothing has been slowed down and nothing has been sped up.
You're not the first person to a) believe that there is such a thing as a 24p standard definition video format (there isn't), and b) believe that because something is recorded at 23.98, it should be treated like a film transfer, even if it isn't one. The only time "pulldown" becomes an issue with sound sync is when the picture is shot on film at 24fps, because telecine slows the running speed of the picture to 23.98 during the transfer. Therefore, the sound must be slowed down the same amount in order to stay in sync. With video, there is no telecine, no "pulldown," and thus no speed change.