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  1. I've always created a 24 frame sequence If I had to import 23,97 video. Render the output in 24. Never had any issue. The same goes for 29,97 and 30.
    Dunno. I started to wonder maybe I actually do mess it up. I know about lower and upper field, audio sync and all that

    Do Premiere and other editors interpret and deal the footage's fps when you import so you don't have to worry about this? Or you do?
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  2. Originally Posted by Dagger7 View Post
    I've always created a 24 frame sequence If I had to import 23,97 video. Render the output in 24. Never had any issue. The same goes for 29,97 and 30.
    Dunno. I started to wonder maybe I actually do mess it up. I know about lower and upper field, audio sync and all that

    Do Premiere and other editors interpret and deal the footage's fps when you import so you don't have to worry about this? Or you do?


    Yes it matters - That will give you a duplicate frame (and stutter) every 1001 frames

    Editors usually conform the assets to the timeline and export settings. So PP (all NLE's, really) will add those duplicate frames to make up 23.976 to 24.000

    Generally you want to use correct matching settings for everything , especially if you only have 1 type of asset
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  3. Originally Posted by poisondeathray View Post
    Originally Posted by Dagger7 View Post
    I've always created a 24 frame sequence If I had to import 23,97 video. Render the output in 24. Never had any issue. The same goes for 29,97 and 30.
    Dunno. I started to wonder maybe I actually do mess it up. I know about lower and upper field, audio sync and all that

    Do Premiere and other editors interpret and deal the footage's fps when you import so you don't have to worry about this? Or you do?


    Yes it matters - That will give you a duplicate frame (and stutter) every 1001 frames

    Editors usually conform the assets to the timeline and export settings. So PP (all NLE's, really) will add those duplicate frames to make up 23.976 to 24.000

    Generally you want to use correct matching settings for everything , especially if you only have 1 type of asset
    1001 frames? Every 42 seconds?
    Conform? Is this the modify clip option? This will fix the stutter and duplicate frame issue?

    So when I drop footage to the timeline that has a different fps Premiere will run frame sampling or 2 other options if I choose so?
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  4. Originally Posted by Dagger7 View Post
    1001 frames? Every 42 seconds?
    Yes every 1001 frames because 23.976 is actually a rounded abbreviation for 24000/1001. It's 24000/1001 FPS vs. 24/1 FPS . You can test it out yourself and verify that the duplicates are there

    Conform? Is this the modify clip option? This will fix the stutter and duplicate frame issue?
    No, I'm referring to "automatic" conforming. All editors alter/change the footage to match the sequence settings. If you drop 25p footage on a 24.0p timeline, it would drop a frame every second. This would cause jumps in the motion. All editors by default change the framerate to match the sequence (or timeline) settings by inserting or dropping frames. Sometimes duplicates or blends, depending on what settings you have set

    Modify clip and interpreting the footage means keep the same frames, but assume a different framerate. ie. playback faster or slower. So if you interpret 23.976 as 24.0 fps, the speed will be faster, duration shorter. Interpreting the footage framerate means changes the framerate without inserting or dropping frames. This is one way of speeding up 23.976p to 24p

    The other way most people do it is to use the correct settings for the footage. ie. changing the sequence settings to correctly match the 23.976p footage will fix the issue (ie. use a sequence setting matching your clip , and export with the same settings). There is an option to automatically make the correct sequence matching the footage - "new sequence from clip"

    Was there a reason why you wanted 24/1 vs. "23.976" ?
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  5. Member Cornucopia's Avatar
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    Also, unless you plan on outputting for cinema, there almost never is a reason to use true 24fps. May have changed more recently, but what I have experienced is vast majority of consumer cams that offer a 24fps option are really providing 23.976 (aka 24000/1001), and so should be interpreted as such. If it is wrong, you could tell because audio would drift out of sync.


    Scott
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  6. Originally Posted by poisondeathray View Post
    Originally Posted by Dagger7 View Post
    1001 frames? Every 42 seconds?
    Yes every 1001 frames because 23.976 is actually a rounded abbreviation for 24000/1001. It's 24000/1001 FPS vs. 24/1 FPS . You can test it out yourself and verify that the duplicates are there

    Conform? Is this the modify clip option? This will fix the stutter and duplicate frame issue?
    No, I'm referring to "automatic" conforming. All editors alter/change the footage to match the sequence settings. If you drop 25p footage on a 24.0p timeline, it would drop a frame every second. This would cause jumps in the motion. All editors by default change the framerate to match the sequence (or timeline) settings by inserting or dropping frames. Sometimes duplicates or blends, depending on what settings you have set

    Modify clip and interpreting the footage means keep the same frames, but assume a different framerate. ie. playback faster or slower. So if you interpret 23.976 as 24.0 fps, the speed will be faster, duration shorter. Interpreting the footage framerate means changes the framerate without inserting or dropping frames. This is one way of speeding up 23.976p to 24p

    The other way most people do it is to use the correct settings for the footage. ie. changing the sequence settings to correctly match the 23.976p footage will fix the issue (ie. use a sequence setting matching your clip , and export with the same settings). There is an option to automatically make the correct sequence matching the footage - "new sequence from clip"

    Was there a reason why you wanted 24/1 vs. "23.976" ?
    So "automatic" conforming and Modify clip and interpreting the footage will cause the same effect aka slower or faster?

    So ok 23.976 fps drops frame now and then. Can't I reorganise the frames into 24 fps just keep all the frames in tact but changing the timing? Isn't that an option?

    Then how do people deal with 23.976 fps, 24 fps, 29.976 fps, 30fps or 60 fps footage on the same timeline?

    Yeah I use Voukoder and for some reason 23.976 sequence always hangs the render. Any other FPS works just fine.



    It bogs the minds what this 60 year old bullshit from the time when color was introduced in the US doing in the 21st century
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  7. Originally Posted by Cornucopia View Post
    Also, unless you plan on outputting for cinema, there almost never is a reason to use true 24fps. May have changed more recently, but what I have experienced is vast majority of consumer cams that offer a 24fps option are really providing 23.976 (aka 24000/1001), and so should be interpreted as such. If it is wrong, you could tell because audio would drift out of sync.

    Scott
    Yeah I've read about this. Yeah like I said it bogs the mind what this bullshit is doing in the modern day alongiside with non drop frame / drop frame crap.
    Every monitor, mobile and TV displays run at 60 hz minimum. What the hell is .976 crap is even around for? 24p cinema hmm jerky mess to my eyes. I guess that's why everything is hidden behind shallow focus and motion blur. 30 is much preferred and smoother and divides nicely into 60 not to cause any issues.
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  8. Originally Posted by Dagger7 View Post

    So "automatic" conforming and Modify clip and interpreting the footage will cause the same effect aka slower or faster?
    Yes, manually interpreting the footage speeds or slows down by assuming a new frame rate.


    So ok 23.976 fps drops frame now and then.
    If your original source is 23.976 (aka 24000/1001) , and it was produced correctly, there are no "dropped frames" per se

    Can't I reorganise the frames into 24 fps just keep all the frames in tact but changing the timing? Isn't that an option?
    No, timing will change because 24/1 is not the same thing as 24000/1001

    Unless you re-time the footage keeping the same duration using optical flow or similar (can produce artifacts). This generates new inbetween frames using motion vectors or now there is newer technology (neural nets) - it's essentially a resampling of frame times

    Slowing down or speeding up footage is the "best" because there are no artifacts and the audio difference is negligible for 24/1 vs. 24000/1001 when using high quality resampling methods


    Then how do people deal with 23.976 fps, 24 fps, 29.976 fps, 30fps or 60 fps footage on the same timeline?
    Depends on what the output goal is, depends on specific details of the project

    If you just drop the footage on the timeline, all NLE's convert to whatever the project/sequence settings are - and there are multiple methods of standards conversions, but the most commonly used ones by default is dropping/adding and blending frames



    Yeah I use Voukoder and for some reason 23.976 sequence always hangs the render. Any other FPS works just fine.
    Haven't used it in a while, but it worked ok for me, maybe some other issues going on



    Originally Posted by Dagger7 View Post

    Every monitor, mobile and TV displays run at 60 hz minimum.

    Actually some cinema displays can display at 24.0Hz, or 23.976Hz . (They also can display other judderless rates such as 120.0 Hz and 119.88Hz) . There is 24/1 content available to public - eg. some BD's are 24/1 . Others are 24000/1001
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  9. Slowing down or speeding up footage is the "best" because there are no artifacts and the audio difference is negligible for 24/1 vs. 24000/1001 when using high quality resampling methods
    Yes, manually interpreting the footage speeds or slows down by assuming a new frame rate.
    So the best way is just to drop it on the timeline or interpret the footage cos they produce the same result?

    What are those high quality resampling methods? Premiere doesn't use one?
    Last edited by Dagger7; 8th Aug 2021 at 11:44.
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  10. Originally Posted by Dagger7 View Post
    Slowing down or speeding up footage is the "best" because there are no artifacts and the audio difference is negligible for 24/1 vs. 24000/1001 when using high quality resampling methods
    Yes, manually interpreting the footage speeds or slows down by assuming a new frame rate.
    So the best way is just to drop it on the timeline or interpret the footage cos they produce the same result?
    The "best" way is to keep it 23.976. Done. No side effects - period. It's perfect.

    If someone had a gun to your head and you had to change it to 24/1 for some reason , then the next best is arguably to interpret the footage

    Just dropping a 24000/1001 asset on a 24/1 timeline vs. interpreting footage does NOT produce the same result - that's the point

    If you drop 23.976 footage on a 24p sequence/timeline, you get a duplicate frame every 1001 frames

    If you interpret the footage to 24p, on a 24p timeline - that is changing the speed, but at least there are no duplicate frames or glitches. The negative is duration is changed and audio has to be resampled to keep sync


    What are those high quality resampling methods? Premiere doesn't use one?
    I think it's ok for small changes, but an audiophile might disagree and resample the audio in dedicated audio tools

    The magnitude is not as large as say, PAL vs. NTSC - 25 vs. 24000/1001 speed changes , so the potential problems are smaller in magnitude.
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  11. If you drop 23.976 footage on a 24p sequence/timeline, you get a duplicate frame every 1001 frames
    But the audio in tact / in sync? The only issue is duplicates ever 42 seconds?

    If you interpret the footage to 24p, on a 24p timeline - that is changing the speed, but at least there are no duplicate frames or glitches. The negative is duration is changed and audio has to be resampled to keep sync
    So the video plays tiny bit slower over an hour and audio get dysinced? Video can't get fixed? But audio can? I'm confused. And Premiere doesn't resample the audio?
    If you interpret the footage doesn't mean both audio and video will be slowed down therefore keep being in sync?
    Last edited by Dagger7; 8th Aug 2021 at 13:39.
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  12. Originally Posted by Dagger7 View Post
    If you drop 23.976 footage on a 24p sequence/timeline, you get a duplicate frame every 1001 frames
    But the audio in tact / in sync? The only issue is duplicates ever 42 seconds?
    Yes

    If you interpret the footage to 24p, on a 24p timeline - that is changing the speed, but at least there are no duplicate frames or glitches. The negative is duration is changed and audio has to be resampled to keep sync
    So the video plays tiny bit faster over an hour and audio get dysinced? Video can't get fixed? But audio can? I'm confused. And Premiere doesn't resample the audio?
    If you interpret the footage doesn't mean both audio and video will be sped up therefore keep being in sync?
    No it keeps sync, it resamples the audio - but the algorithm used in PP is arguably worse than the ones used in dedicated professional audio mastering/engineering software . It's good enough for my ears on small % resamples
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  13. Thanks mate! Really helped me out with this confusion!
    I gotta test how noticeable a duplicate frame is vs slowing down a video by a tiny bit some day haha
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