Latest post Mon, Jan 10 2011 4:57 PM by jasperfdo. 11 replies.
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  • Sun, Jan 9 2011 9:00 PM

    • jbrotman23
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    23.98 vs. 24p masters, STUDENT in need of HELP please!

    Our planned workflow:

    35mm 3 perf -> telecine to HDCam SR true 24p (no audio) -> capture Pro Res 422 24p files -> transcode to DNxHD 36 in Avid -> sync with 48kHz audio recorded at 30fps -> offline edit -> generate EDL -> cinevator HDCam SR tape masters to 35mm print (match 30 fps Pro Tools mix to film soundtrack)

    Through a miscommunication we ended up with 23.98 SR masters and, consequently, 23.98 Pro Res files.

    We can't afford to re-telecine or video capture so...

    Would it be better to convert our Pro Res files to 24p (and if so, how?), sync with our audio, edit, and then have the post house simply match the 23.98 tape to the EDL appropriately for film out?

    Or should we convert our audio to 29.97 (in Pro Tools, I'm assuming), sync with our 23.98 footage, edit, and then have the post house pull our audio back up to 30 when going out to film?

    My concern is that the conversion of footage would be more problematic/less trustworthy simply because I don't know if Avid is capable of doing such a conversion.

    Any help would be very much appreciated. We need to get moving ASAP. Thank you!

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  • Sun, Jan 9 2011 9:43 PM In reply to

    • jasperfdo
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    Re: 23.98 vs. 24p masters, STUDENT in need of HELP please!

    If the lab did a telecine and created HD-CAM tapes, those are most likely 23.98.  Production sound should have then been recorded at 48.048 so Avid can pull down properly to match your project.  Do the entire project 23.98 and then go back to film - everything will work.

    IF you need to adjust audio to match, you can use the tool from Michael Phillips to re-stamp the audio files for proper pull down.  I've had to do this before when I received tapes from the lab and the production sound was 48K. The audio was .01% off.

    http://www.24p.com/downloads/BWF_recording_rates.pdf

    The tool should be on his site somewhere.

     

     

    MacBook Pro Retina / El Capitan / 16GB RAM / G-Studio Drive System / Media Composer 8.6.x [view my complete system specs]

    kyler boudreau | www.theatereleven.com

     

     

  • Sun, Jan 9 2011 10:03 PM In reply to

    • MichaelP
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    Re: 23.98 vs. 24p masters, STUDENT in need of HELP please!

    While a transfer can be done at 23.976 or 24, if not requested it is most likely 23.976. Seeing as you did not record your original sound files at 48.048 during production, you cannot "stamp" as 48.048 at this point of the process. You will need to stamp them 47.952. Also, the "stamp" tools I put on my website at 24p.com are quite old and today I prefer to use Sound Devices' WaveAgent application which does this and a lot more. It can be downloaded from www.sounddevices.com

     

    Michael

    24p.com

  • Sun, Jan 9 2011 11:29 PM In reply to

    • jbrotman23
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    Re: 23.98 vs. 24p masters, STUDENT in need of HELP please!

    Thank you both for your quick response!

    So once we convert our audio to sync with our 23.98 footage, we export our audio from Avid for final Pro Tools mix at what kHz? 47.952? Also, doesn't this conversion require a pitch correction of some kind since the speed is being changed?

    Finally, once we're ready, do we convert our final mix back up to 48 kHz in Pro Tools or do we let the post house handle that?

  • Mon, Jan 10 2011 1:36 AM In reply to

    • MichaelP
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    Re: 23.98 vs. 24p masters, STUDENT in need of HELP please!

    Once imported into the Avid, it becomes 48kHz audio in sync with 23.976 media. Most productions don't care about pitch correction for .1% speed difference.

     

    Michael

    24p.com

  • Mon, Jan 10 2011 3:04 AM In reply to

    • jasperfdo
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    Re: 23.98 vs. 24p masters, STUDENT in need of HELP please!

    Michael is the pro, but let me tell you that I went through all of this worrying right out of film school on my first film based feature. Your entire workflow should stay at 23.98 until it goes back to film (if it ever does).

     

    And beware - you will run into the occasional old school sound designer in LA that doesn't know what they are talking about, and they could even freak out if you give them 23.98 source - it has happened to me.  Ignore them! 23.98 is the way to go and stay. =)

    MacBook Pro Retina / El Capitan / 16GB RAM / G-Studio Drive System / Media Composer 8.6.x [view my complete system specs]

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  • Mon, Jan 10 2011 3:08 AM In reply to

    • jbrotman23
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    Re: 23.98 vs. 24p masters, STUDENT in need of HELP please!

    Okay so just for clarification my workflow would be:

    Create 23.98 Avid project -> transcode 23.98 ProRes footage to Avid codec -> re-stamp 48 kHz audio at 47.952 -> bring into Avid and sync with footage -> export audio as is (47.952) for Pro Tools mix -> create 24P cutlist from 23.98 footage (because it shouldn't matter that the footage isn't 24p) -> take cutlist and 47.952 mix to post house for output from tape to film and the post house will take care of the timing conversions for us.

    Correct?

    Thanks for you patience, I'm really new to this workflow.

  • Mon, Jan 10 2011 1:56 PM In reply to

    • MichaelP
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    Re: 23.98 vs. 24p masters, STUDENT in need of HELP please!

    Create 23.98 Avid project ->
    YES

    transcode 23.98 ProRes footage to Avid codec ->
    YES

    re-stamp 48 kHz audio at 47.952 ->
    YES

    bring into Avid and sync with footage ->
    YES

    export audio as is (47.952) for Pro Tools mix ->
    NO. Audio is now 48kHz for rest of post process and will be treated as such.

    create 24P cutlist from 23.98 footage (because it shouldn't matter that the footage isn't 24p) ->
    YES

    take cutlist and 47.952 mix to post house for output from tape to film and the post house will take care of the timing conversions for us.
    YES - audio wil be 48kHz but they will adjust for all outputs and speed changes.

     

    Michael

    24p.com

  • Mon, Jan 10 2011 2:49 PM In reply to

    • jasperfdo
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    Re: 23.98 vs. 24p masters, STUDENT in need of HELP please!

    To expound on Michael's comments above, once you restamp your audio (or change it with the newer method he mentioned) and bring it into Avid, Avid will adjust it so that it is 48K now.  That .01% adjustment will be done to all of the audio as it is imported into Avid.

    When you take it back to the lab, both the 23.976 picture and the 48K audio will be upped to 24 and 48.048.  And this doesn't affect pitch or anything like that. The only way you ever notice that .01% on a film is if the audio is .01% off from picture.  On a long take, picture and audio beging to drift ever sol slightly.

     

     

    MacBook Pro Retina / El Capitan / 16GB RAM / G-Studio Drive System / Media Composer 8.6.x [view my complete system specs]

    kyler boudreau | www.theatereleven.com

     

     

  • Mon, Jan 10 2011 4:28 PM In reply to

    • MichaelP
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    Re: 23.98 vs. 24p masters, STUDENT in need of HELP please!

    Just to be clear, there should never be drift at 23.976 or 24 as long as you control the sample rate to frame rate. In all cases, the lab knows what to do as they need to deliver all the time 23.976, 24 and 25 for worldwide programming.

    One quick thing, when importing 47.952 or 48.048 audio, make sure your audio import settings are set to adjust the .1% variants.

     

    Michael

    24p.com

  • Mon, Jan 10 2011 4:36 PM In reply to

    • jbrotman23
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    Re: 23.98 vs. 24p masters, STUDENT in need of HELP please!

    MichaelP:

    export audio as is (47.952) for Pro Tools mix ->

    NO. Audio is now 48kHz for rest of post process and will be treated as such.

    take cutlist and 47.952 mix to post house for output from tape to film and the post house will take care of the timing conversions for us.
    YES - audio wil be 48kHz but they will adjust for all outputs and speed changes.

    If Avid is doing the pullup to 48 automatically does that mean it's going to be playing the 23.98 footage at 24fps as well?

    If so, to avoid any drifting problems as Jasper states, is it possible to just edit at 23.98 fps playback with 47.952 audio or, using your suggested workflow, will the post house simply up the footage to 24 and leave the sound at 48 since it's already there?

    I apologize for the back and forth, I'd just like to get our film and audio back to where it started cleanly, if possible.

  • Mon, Jan 10 2011 4:57 PM In reply to

    • jasperfdo
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    Re: 23.98 vs. 24p masters, STUDENT in need of HELP please!

    No it is not playing the footage at 24.  The video remains the SAME as from the lab. When you import the audio and tell it to adjust pull down as Michael specified, it permanently changes you audio.  The audio then contained in your Avid MediaFiles folder is then different than the raw copy of the audio not imported.  

    Hope that makes sense. 

    Once you import your audio and let Avid adjust it, you edit away and never worry about anything.  The only time you'd experience drift is if you import your audio, but do not let Avid adjust the speed.

    One more point to clear any fog: the only reason you are taking your audio to 47.952 is so Avid will slow it down by .01% on import.  Then it matches picture and you're good to go.  No quality harm - no problems.

    MacBook Pro Retina / El Capitan / 16GB RAM / G-Studio Drive System / Media Composer 8.6.x [view my complete system specs]

    kyler boudreau | www.theatereleven.com

     

     

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