Creative Communities of the World Forums

The peer to peer support community for media production professionals.

Activity Forums Avid Media Composer converting a subclip from 29.97 to 23.976

  • converting a subclip from 29.97 to 23.976

    Posted by Henry Barrial on August 4, 2012 at 2:46 am

    I’m new to AVID and am working on a low budget feature film shot on an Arri Alexa at 23.976. I’m the director but was forced to essentially assistant edit (I am a recent convert from FCP and had to take a crash course in MC6, i.e. Lynda.com). This was, of course, a terrible idea born out of necessity. We are in MC6 and I “AMA” linked to the ProRes footage and it worked like a charm. Due to my naivete I accidentally did a sync (audio to video) creating subclips in a 29.97 project. I meant to do this in a 23.976 project. So, when I want to play back the subclips in 23.976 (we created a new 23.976 project and copied everything in 29.97 project over) there is a jitter effect to the video which is when I discovered my mistake. My big question is, can I convert those 29.97 subclips to 23.976 in a quick and easy fashion? If so, how. If not, does that mean that I need to manually matchframe each subclip and then re-sync (will they get thrown off?) all of that footage? It took me three weeks to sync and log the first time around (no time code sync during production) so I’m already suffering from PTSD.

    Can anyone offer an alternative solution to re-syncing everything manually so that my subclips become 23.976?
    Thanks!
    Henry “the naive one”

    Job Ter burg replied 13 years, 11 months ago 4 Members · 16 Replies
  • 16 Replies
  • Michael Phillips

    August 4, 2012 at 11:58 am

    Welcome to the world of low-budget filmmaking! And unfortunately there is no way to just convert those clips to be at their native rate as they have already done through two conversions – the first one when you opened 23.976 clips in a 29.97 project – 2:3 pulldown was added. Now opening those clips in a 23.976 does another pass – unfortunately it does not seem that Media Composer is undoing what it did in the first place and doing the mix and match slightly differently. The mix & match feature is a great one – but does still have areas of improvement for edge cases such as this one.

    Also, you will want to make sure the clips are edited natively from the get-go for EDL purposes and such to ensure a frame accurate conform in the end.

    So I regret saying that you will have to start the syncing process over, if you want to remove the stutter created by the frame rate conversion. I am also a little surprised that if you could shoot on an Alexa why you couldn’t jam sync timecode to the audio recorder. But it’s a little late for that. This is a case of saving a little money up front costs more in the end – usually time. Not trying to sound condescending, just some education for others who might read this post and learn for their first film.

    Michael

    Michael Phillips

  • Bouke Vahl

    August 4, 2012 at 1:35 pm

    quick thought.
    Avid exports Wave as BWF.
    So if the clips are synced, you can export to wave and import those waves. (perhaps after an autosequence)
    They then have the same TC (well, SAMS) as the synced clips.
    Since the timestamp in BWF is NOT tc but Samples after Midnight, they should line up with the original 23.976

    Bouke

    https://www.videotoolshed.com/
    smart tools for video pros

  • Henry Barrial

    August 4, 2012 at 4:06 pm

    So Michael, last night we created a new 23.976 project, copied the 29.97 project and pasted it in the 23.976. All the RAW audio & video converted to 23.98 but the subclips did not. I then matched frame manually for both audio and video. The subclips retained their sync and I was able to cut the process in half by not having to re-log the footage. Is this match framing going to present a problem with an EDL later down the line?

    Thanks for your earlier reply.

    Henry

  • Michael Phillips

    August 4, 2012 at 4:50 pm

    It seems you are going the mix & match route which is fine in order to not have to resync and such, and all metadata logged will still be there. The only side-effect may be a +/-1 frame type adjustment due to the 30->24 conversion, and you will still have whatever subtle stutter in the footage as it is a motion effect that is being applied to the sources. If you look in the timeline you will see that all the clips have a little green dot on them (or should). You may have gotten lucky and the original frame rate of the clip (23.976) persisted through the 29.97 project back to 23.976 and you will not have any motion adaptors. Check your timeline to see – if not, there will be no timecode adjustment to the clips. If you transcoded the material in the 29.97 project, then it becomes as though it were a native 29.97 clip back in your 23.976 project and subject to timecode conversions.

    Bouke raises a very interesting workaround with AutoSequence and then Autosyncing all the picture only clips to the single BWF file… hmmmm. Gonna have to try that one.

    Michael

    Michael Phillips

  • Henry Barrial

    August 4, 2012 at 5:14 pm

    I’m a novice so that is a little confusing. What I think you’re saying is export my audio/video subclip as a wave file but I don’t know what an autosequence is, so I’m a little lost there, then import the wave and throw it on a new timeline and it should be in 23.976?

  • Henry Barrial

    August 4, 2012 at 7:35 pm

    Lost the stutter. Everything plays back fine. And since this is all done through AMA linking it shouldn’t be an issue later on (I hope) with generating an EDL.

    I do not have a green dot on my newly matchframed subclips. Should the green dot be there and if not is that a problem?

  • Michael Phillips

    August 4, 2012 at 8:11 pm

    If you don’t have a green dot, then all is good. Since you didn’t transcode in the 29.97 project, the frame rate persisted through to the 23.976 project and no motion adapters were applied. EDLs will be good as well. You’re all set.

    Michael

    Michael Phillips

  • Henry Barrial

    August 4, 2012 at 9:16 pm

    Michael, thanks again. We will forge ahead with the match frame solution. See,s to be working thanks to the AMA linking. AMA gets a bad rap but I think it’s pretty cool from a former FCP user’s vantage point. Thanks!

  • Michael Phillips

    August 5, 2012 at 12:46 am

    There’s the good and bad of AMA- you were lucky to have not transcoded as the fact it was originally a 23.976 clip would have been lost and you would have had the motion effect adapters and +/-1 frame for EDL.

    Good luck with the rest of the project.

    Michael

    Michael Phillips

  • Henry Barrial

    August 5, 2012 at 4:46 am

    Michael I’ve had a complete reversal in a manner of hours. Just when you think you’re winning…It’s as if AVID is trying to get me, I swear. The new strangeness began with an inability to re-link to audio. In an attempt to keep the editors working, I devised a plan to work on a 2nd computer using a mirrored drive. I would re-link to AMA files in a 23.976 project then email the bin to the editor. It worked one time and then we were cut off. I can re-link AMA video but, even though I had already successfully re-linked audio on a previous scene, that workflow suddenly stopped being successful. For some reason AVID lost the ability to re-link any audio file on the mirrored drive. I’ve tried it on multiple scenes now.

    So, I decided finally to sync the next scene from scratch in a 23.98 project, as I had at the beginning of this process when I committed the dreaded 29.97 error, and sent that bin over to my editor and that didn’t work (even though we had successfully accomplished that once previously). The editor had trouble reconnecting and matching back to audio. Same crappy messages I was getting with a window popping up that asks me to change the settings (which I do) when I simply try to “re-link.” Or it gives me a message that it is: “Unable to relink AMA clip to selected file. It may be incompatible with the original. (i.e. file type, edit rate, track list, duration)”

    I am not even able to re-connect media files to manually selected audio clips even though the audio name has not changed.

    I am at my wits end. I was warned not to jump into MC6.01 but it was out of necessity with the editors. I went to 6 because it can handle the ProRes natively (supposedly).

Page 1 of 2

We use anonymous cookies to give you the best experience we can.
Our Privacy policy | GDPR Policy