Delivering mixes at multiple frame rates

[Tim R.]

I'm just finishing mixing a short (12 minute) documentary, and the producer has asked for mixes to be delivered at both 23.976 (the original format) and 24 fps. What is the best way to accomplish this? My inclination is that this should be done along with the video when that is transcoded to 24.

[JFreak]

I don't think you have any other choice than two bounces.

[Frank Kruse]

Originally Posted by Tim R.

I'm just finishing mixing a short (12 minute) documentary, and the producer has asked for mixes to be delivered at both 23.976 (the original format) and 24 fps. What is the best way to accomplish this? My inclination is that this should be done along with the video when that is transcoded to 24.

Import your original master(s) into an empty 24fps session and select the +0.1% pull up preset under SRC. (beware, the SRC presets are broken in some recent PT21.x versions. Make sure you use 21.10 for this.
The result will be your mix sped up to 24fps (and shorter) to match the pulled up picture.
I wouldn't leave this to picture dept unless they know exactly what they are doing.
Best is to have the 24fps video so you can check sync (head and tail pops).
Don't mess with time-stretch plugins. The tiny shift is barely noticeable and the SRC will maintain 100% sync unlike many of the stretch-squeeze plugins.

[its2loud]

Hey Tim,

This ⬆️

Or you can deliver the 23,98 version and have the picture editor spit out the 24 frame version. The pitch shift is up to you. It’s such a small amount.

[kosmokrator]

What Frank said.
I’d just add that I would insist on getting a ref video in both target FPS rates.
If not you can never be sure everything is in sync.
And blame will be on you.

As Frank pointed out, the issue can be a simple PT bug.

[Cheesehead]

Hi Frank,


When you say

beware, the SRC presets are broken in some recent PT21.x versions

What specifically is broken?


I've always used the method you describe for making 23.98 deliverables fron 24fps, but I tried one yesterday and it doesn't match the ref QT the picture dept have sent.


Now I'm not sure if they've prepped their picture incorrectly, or Pro Tools is faulty?


I'm using PT2021.7.

[garret]

Originally Posted by Cheesehead

Hi Frank,


When you say

What specifically is broken?


I've always used the method you describe for making 23.98 deliverables fron 24fps, but I tried one yesterday and it doesn't match the ref QT the picture dept have sent.


Now I'm not sure if they've prepped their picture incorrectly, or Pro Tools is faulty?


I'm using PT2021.7.

Some versions of Pro tools are simply not selecting the correct sample rate that you choose for the pull up or pull down. You can see this when you try to select the pull up/down, the incorrect sample rate will appear. You can fix this by either using custom mode or upgrading your Pro tools version.

[smurfyou]

I'll repeat that you should get reference picture. Even if they tell you you don't need it or it's not ready yet. It's a simple process but you need to verify it's correct.

[Tim R.]

So is there a risk of lip-sync issues when this is left to the picture editor to output a 24 fps version from 23.98 with mixed audio?

[JFreak]

No. The difference is so small that if there would be a lip sync issue on the final converted version, someone has screwed up, not the format.