Editing with 24p and 24pn

N

Nonsense

Active member
Soon I'll be editing something that we shot on the HVX today. Part of it was shot as 24pn directly to the cards and everything else was shot as 24p going to a firestore.

we'll be editing on Avid. I was told this might be a problem. does anyone know if it is impossible to edit native footage with non-native footage?

thanks.

-Marshall
 
Thanks guys. I'll update you with progress.

Any starter points as to how to convert the 24pn to 24p within AVID?

-marshall
 
You'll have to bring all the 24pN media into an Avid 720p/23.976 project, and all the 24p media into an Avid 720p/59.94 project. From here, you have two options, depending on which project you'd ultimately rather work in. Either process results in breaking the timecode on your clips, so if you need to go back to work on a project at a later date, plan on archiving the media as created by the Avid, and not just the media from the camera.

First option - work in the 59.94 project:

1) In the 23.976 project, select all the clips you'd like to use, and export them as QT reference files with the setting "Same as Source".

2) Close your 23.976 project, launch the 59.94 project, and import all the QT refs you just exported. The Avid will pad out 24p clips with 2:3 pulldown to create 59.94 media. This is how "24p over 60p" works, so the footage looks exactly the same. There's no quality loss (that I've been able to discern), as it's merely duplicating frames and copying them to another media file. There shouldn't be any decompression/recompression going on. The QT reference is simply an intermediary file.

Second option - work in the 23.976 project:

1) From your 59.94 project, select all your clips you want to use, and export them as QT references, again set "Same as Source".

2) Close the 59.94 project, launch your 23.976 project, and import the QT reference files.

(This is the part that takes a little longer than the first method, but I think makes it better, because your files end up being 2.5x smaller...)

3) Create two bins, one called "Good" and one called "Bad".

4) Play each individual clip that you imported, and check that the proper frames were stripped out on import. This is the exact opposite of the process above, where you were adding frames in to fill out to 60 frames per second. Now, you're removing the 2:3 pulldown that is in the "24p over 60p" clips to create native 24p media. The problem is that sometimes, the original clips didn't start on the right frame for pulldown removal, so you'll see a weird stutter that will reveal itself right away. As you play the clips, move the ones that play back properly into your "Good" bin, and the ones that don't play right into your "Bad" bin. Most of them should import properly on the first try, but from my experimentation, there's usually about 20% that don't come in right on the first try. Jot down the names of the clips in your "Bad" bin.

5) Go back into your 59.94 project, and create a new bin there called something like "Re-Export". Move the clips into it that didn't import properly into your other project. You now need to change the start points of these clips before re-exporting, so that the cadence is properly removed.

6) In your "Re-Export" bin, go into Script mode. Select all the clips. Press "T" to mark the clips with ins and outs. Press "Q" to jump to the inpoints of all the clips. Press "4" to move forward one frame. Press "E" to mark a new inpoint on all the clips. Now, re-export all the clips as you did before, making sure that you have "Use Marks" enabled--otherwise the Avid will ignore your ins and outs. You probably should delete all your original QT reference files so you don't mix any of them up with these new ones.

7) Jump back into your 23.976 project, and import the marked clips you just created. Follow the same procedure you used above to check that the clips play properly, and if any of them don't, you'll have to go back to your 23.976 project and re-mark/re-export the clips. This time, however, you'll step forward two frames before marking an inpoint. You may have to go to three frames if going two doesn't work, but I've never had to go more than two.

I know it seems like a lot of steps, but it's really not that bad once you get into the flow of it. And again, I don't think you really see any quality loss, because you're only adding or extracting frames, depending on the method you choose. As I said, I usually go 59.94 --> 23.976 because of the space savings, and the ability to work with discrete frames. Hope it works for you, and let me know if you have any problems. Enjoy!
 
Dear Cbrougham,

I'm indebted. You're why this site kicks so much ass.

Can't thank you enough.


marshall
 
I thought Avid's main advantage over the competition was the ability to work with multiple formats within the same timeline?
 
Shouldn't be; Vegas and EDIUS are both far ahead in that regard. In Vegas and EDIUS you can put anything on the timeline; you can mix 24p and 30p and 60i, you can mix standard-def and high-def, in Vegas you can pull in a .VOB off of a DVD, and throw in an animated .GIF, and a flash video, and a quicktime movie. It'll automatically scale, shrink, slow down, speed up, or otherwise conform the footage to match whatever the timeline is set to.

EDIUS will strip out 2:3 or 2:3:3:2 pulldown from an MXF file automatically. Avid can't even edit HVX 1080/24P on a 24P timeline yet.
 
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