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Importing a 23.976 NTSC EDL into Avid
Has anyone ever been able to import a 23.976 EDL into the Avid? The keyword here is IMPORT.
Using EDL Manager, open a 23.976 EDL and send it to Avid as a sequence. Note how the record and source timecodes don’t match and get progressively worse as you go down the timeline.
Try this if you think I’m crazy…
Make a simple Sequence of a few edits in a 23.976 NTSC project. Output an EDL to the EDL manager. Then try the simple task of sending the EDL right back into the Avid Media Composer as a NTSC 23.976 Sequence. Then drop this new sequence on a layer about the original sequence and note how different they are.
If it works for you, please let me know so I can track this one down.
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9 Replies
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Which versions of MC and EDL Manager?
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If you make an EDL from a NTSC 23.976 project using the START timecode column it will be 30fps as NTSC is always 30fps. The 24fps timecode lives in a TC24 column and should be selected when making the EDL. Same for record side. Is this what you are making?
Also be sure that once you have the proper 24fps EDL in EDL Manager that you save it out as an EDL. Clear EDL Manager, and then import the EDL and do the import process from there.
Michael
Michael Phillips
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I have traced my problem to my own assumptions based on logic and reason. Having worked on Avid as long as I have, I should have known better than to assume anything. My problem can be traced to the fact that I work on other systems that do follow logic and reason, and applied that to the Avid by mistake.
My first assumption was that a 23.976p NTSC project was running timecode at 23.976 frames per second. This appears not to be true. If one were to create a new sequence, the Master TC1 track counts 30 fps. Yes, there is a 24 fps timecode track, but it is hidden by default and must be shown and selected in the composer.
To further illustrate my point… if you import a TGA sequence into a 23.976 NTSC project, the result in a SD 23.976 NTSC clip who’s timecode track is 30 fps. ¿Por qué? This makes no sense to me. Sure, you can duplicate the START column to the TC24 column in some arcane secret handshake technique only known to a select few wizards to generate a 24 fps timecode track… but this is ridiculous… I’m in a 23.976 project! Am I not?
What drives me crazy (yes, I am crazy) is the fact that if one were to create a 23.976 1080 project, then the timecode behaves as one would expect. The Master TC1 is indeed 23.976 fps and uses 23.976 timecode, not 29.97 like the faux 23.976 NTSC project does. Same with imported sequences and source clips. Genuine 23.976 timecode by default.
So why does the 23.976 NTSC project behave differently than the 23.976 1080 Project?
Fine. So be it. Moving on.
Then I came up with a brilliant idea! Since the HD projects DO handle timecode correctly. Why don’t I just import the EDL into a 23.976 HD project and re-format the sequence to a 23.976 SD sequence, decompose and wala! Damn, I’m brilliant! Sure enough, the 23.976 EDL imported correctly, the sequence lined up accurately and then this… “Could not change the format of sequence NICOLE KIDMAN SEX TAPE 24P. This conversion from HD to SD is not supported”
Brick wall again… brought to you by the people in Tewksbury who obviously don’t get around to the real world very often to notice that there is a 30 to 24 fps workflow happening out here.
Now… let me attempt to explain why there is a brick wall. Stay with me on this.
NTSC has only one frame rate. There is no such thing as 23.976 NTSC. It doesn’t exist. There are various ways of preserving 23.976 moments in time inside 59.94 fields, AKA Pulldown and Advanced Pulldown. In the end, the tape always runs at 29.97 fps. Yes, there was a time when we all used videotapes, and some of us still do!
So, to be able to edit 23.976 moments in time per second and display it on a NTSC monitor requires some behind the scenes trickery. First, pulldown is removed during capture to create the 23.976 media that you can edit with. Second, the 23.976 output has pulldown inserted into it in real time to allow playback on a NTSC monitor, and most importantly… onto a NTSC videotape. Remember, NTSC is 29.97 only.
But what we tend to forget is that since the VTRs are all running at NTSC 29.97 fps, their timecode is also running at 29.97. What the Avid sees when it captures and outputs to tape is 29.97. It has to, or it wouldn’t be able to control the VTR. Therefore, a 23.976 NTSC project on the Avid is really not much different than a 30i NTSC project, as far as timecode goes.
However, this is no excuse. There is no reason that the defacto TC tracks can’t be 23.976 like their HD brethren. In my opinion, they should. Or, if that is too difficult for the tewkburians, the 24 TC track should pop out from the screen and hit me in the forehead when I’m in a 23.976 NTSC project.
In conclusion, there is still NO way to take an existing 30i NTSC project and convert it to a 23.976 NTSC project… that I know of… on an Avid. If Avid is baffled by this conundrum of a workflow, I suggest the sit down in front of an Autodesk Smoke. This tool for grown-ups has a great 30i to 24p workflow that… well… works! There are two different ways of importing footage from VTR. You can remove pulldown from 29.97 VTRs, or you can bring in native 23.976 from VTRs that support native 23.976 (HD decks). You can convert 29.97 EDLs into 23.976 EDLs. You can import clips at any frame rate, selectively remove pulldown on clips and all kinds of other tools required to conform projects in the real world.
Oh… and you can downconvert a sequence from HD to SD! Imagine!
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Unlike other systems, the Avid maintains the fact that NTSC is by its very definition a 29.97 DF or NDF system in order to recapture any sources that may have gotten lost, deleted, etc. It also tracks in that very same project 25, 24, 25 with pulldown, 30 with no pulldown, and more importantly the cadence relationship for every clip to manage the 24 and 30. Although “assuming” that “A” frame falling on 0 and 5 is good… it is a recommendation and not a carved in stone rule that everything abides by. Bad down converts, dubs, etc, will all change that relationship. A one field slip on an “A” frame in a dub makes it a “C” frame. Wrong cadence in a 29.97 to 24 conversion will create a +/-1 frame offset. Add to that the additional matchback process that does a +/- 1 frame adjustment, you can now be 2 frames out.
Why does a graphic file import follow NTSC conventions? becuase we need to cover all workflows as much as possible. Graphic files can go out to SD tape as a proxy we can track that properly. NTSC is NTSC and as you say HD is HD. 1080p/24 and 23.976 are actual 24 frame counts and that is the reason those count as 24.
Could it be easier – perhaps and certainly in some areas. But you will find no other system that can tracks as much metadata on a per frame baiais as the Media Composer and generate a list on it.
Michael
Michael Phillips
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I feel your pain Paul!
Thanks for sharing your insightful rant ;>) Greaaaaat post!Holy Cow!
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All that metadata isn’t helping me accomplish my goal. And I’m not asking for much, nor do I have some exotic request.
I want to be able to take a 30i project and conform it to a 23.976 NTSC project. This exact task is being done by a room full of people in Burbank using printed EDLs that I convert for them in Smoke.
Metadata or not.
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I feel like i’m missing something here.
isn’t a 24 EDL exact like a 30 EDL, except that the frames are slightly different?
Once you know the cadence of your source, isn’t it just changing the frames a bit?
(assuming NDF and cadence start on 0)
fisrt column NTSC frames, second column 24 frames
0 1 2 3 4, the 24 frames are identical
5 6 7 8 9, the 24 frames – 1
10 11 12 13 14, the 24 frames -2
15 16 17 18 19, the 24 frames -3
20 21 22 23 24, the 24 frames -4
25 26 27 28 29, the 24 frames -5If the cadence starts on another frame, just change the list a bit…
How hard can it be to alter a NTSC EDL yourself in, well, Word? Just convert to a table, sort on frames, do a selective search/replace and convert back to text…What part did i not understand?
Bouke
https://www.videotoolshed.com/
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Yes, the process of converting 30i to 24p timecode is very simple. The task of doing it accurately for hundreds of events (each event has four timecodes) as well as modifying transision durations and prediciting source code matches during timewarp speed change match frame edits… and you best leave it to a computer program to accomplish. Oh, and then toss in Drop-frame timecode and non-standard cadence and you will want to think twice about doing it on paper.
However, that wasn’t the point of this thread. The point is that you can not import a 23.976 EDL in to a 23.976 NTSC Project.
Yes, it’s a simple request and sounds like a logical thing to do… but you can’t.
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I have found more info about this issue from an Avid Whitepaper on Metadata. See…
https://www.avid.com/resources/whitepapers/avidmetadata_wpv2.pdf
They mention that the 23.976p NTSC, 24p NTSC and 23.976 720p all run at 30fps timecode. ONLY 23.976 1080p runs at 24.
In addition, 24p PAL runs at 25.
While I can understand that for technical reasons this is the way they decided to go, there should be a workflow for importing a 23.976 EDL into a 23.976 project. Even if this requires the conversion of 23.976 timecode back to 30 internally. Populate the metadata and your good to go.
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