Skip navigation
mau0968
Currently Being Moderated

Why there's a lenght difference between 24fps and 23,976 fps timelines with the same clip?

Aug 14, 2012 7:40 AM

Tags: #error #frame #sequence #premium #import #ae #premier

I was working on a 23,976fps project and I've tried to import a short  animated sequence of 44 tiff frames in my timeline in my Premiere CS5.

I've imported the sequence, interpreted the footage to 23,976fps (as it was rendered in AE) to check it before sending it to a finish house.

 

First issue. Even if I set the framerate to 23,976, Premiere CS5 shows me 23,98 on interpret footage window. I've assumed it as a rounded number.

 

When I drag the clip to my 23,976 sequence, the clip shows as 43(!) frames length on info panel. It misses one frame. Putting the sequence over the original video, It really misses a frame.

 

I decided to make a test. And placed the same clip, interpreted the same way on a 24fps sequence, and the clip shows as 44 frames length on info panel.

 

How can, the same clip, shows different amount of frames (I'm not talking about time, but simply raw frames), on different timelines? It does not make any sense! If my sequence has 44 frames, It should show as 44 frames independent of the timeline I've imported it. Am I Right?

 

Just for test, I´ve imported the same sequence on AE, and in it shows as 44 frames on a 23,976 timeline. How can I trust Premiere frame interpreting this way?

 

Just one more thing. The scene used as base for the AE animation, has 44 frames, and it was measured and cut from a 30s film on the same premiere that is having this weird behavior.

 

Can anyone explain to me what Just have happened? It´s driving me Crazy!

 

Thanks in Advance

 

Mauricio Mendes

 
Replies
  • Currently Being Moderated
    Aug 14, 2012 4:18 PM   in reply to mau0968

    Before you import the Image Sequence, go into Edit>Preferences>Media... and set the Intermediate Timebase to 23.976.

     
    |
    Mark as:
  • Currently Being Moderated
    Aug 16, 2012 12:53 PM   in reply to mau0968

    There's a long and storied history behind the concept of a drop frame tmecode. It traces its origin to early color TV in the USA, and was a way to get rid of artifacting that was visible on B&W TVs when watching the color signal (color subcarrier).

     

    Basically, by having your intermediate timebase set wrong, you were having PPro drop a frame. That's why you saw the mismatch in frame numbers.

     
    |
    Mark as:
  • Currently Being Moderated
    Aug 16, 2012 3:33 PM   in reply to mau0968

    Why the intrepert footage gives me wrong results?

     

    This is what an Adobe engineer had to say about it.

     

    "For still sequences the intermediate timebase unfortunately gets baked in at a layer below interpret footage and isn't overridden by it."

     
    |
    Mark as:

More Like This

  • Retrieving data ...

Bookmarked By (0)

Answers + Points = Status

  • 10 points awarded for Correct Answers
  • 5 points awarded for Helpful Answers
  • 10,000+ points
  • 1,001-10,000 points
  • 501-1,000 points
  • 5-500 points