Odd 24p Interlacing Problem

[Colione]

On my time line and in the canvas, I get this odd field separation every 4th frame and occasionally every 5th frame. But when I double click the clip to view it in my viewer the field separation is gone. Very baffling. Something must be doing it in the sequence is what I thought. So I turned off all the effects, and tried turning the field dominance to none. Nothing worked. Though still my source clip was perfect and the clips on my timeline are wonky. I have no idea what the deal is. I've included two screen shots to show you what I mean.


I filmed at 24pa, captured at 60i on final cut express. Editing on a 29.97 timeline. Put the files on my ipod, and opened in FCP5 and reconnected the media. I don't think this problem was happening earlier in the project, but now is just the first time I've noticed.


Any idea on how to fix this?



Thanks!!

 

[Loki]

well your first issue was shooting 24pa and then capturing at 29.97...

every 5th frame is combination of the frame directly before and after it. It is part of the pulldown used to conform 24p to 60i.

Four progressive frames look like thiseach letter representing 1 field of the image)

AA BB CC DD

the DVX pulls down to create 5 frames (5 into 30 = easier) so it looks like this:

AA BB BC CC DD

so that 'BC' frame is what you are seeing.

this is normal, but why did you capture at 29.97 if you shot 24pA? If you plan to edit on a 29.97 timeline shoot 24p scene file 5 on the camera..

 

[Colione]

Loki,

Thanks for the tips. But I am only seeing the combination frame in the Timeline, not in my source footage.

I shot 24pa, and captured 29.97 because I was editing on a friends laptop who only had Final Cut Express (no pulldown).

If what you are saying is true, I should see the combination frame in both the timeline and my source footage right? But I am only seeing it in the timeline ... ... what's up with that?!

 

[Loki]

if you are viewing your footage at less than 100% in the canvas or viewer window then it will be way more pronouce, it will look pretty awful. But try stepping through your footage frame by frame in the QT player.. you should notice the interlaced frame doing it that way.. it is harder to see when looking at the full size of the footage.

 

[Colione]

Loki.

Hmmm...you're right. I do see it in the original source footage.

How come I don't see it in the viewer??

 

[Scottdvx100]

24pa should have pulldown removed and be edited in 23.98 timeline.
In the future if you want to capture and edit 24fps footage at 29.97 then use 24p (F5) mode.
If you want your captured footage to be changed to 23.98, select clips in bin and go to tools -> remove pulldown. not sure if this works for footage originallky captured in Express.
If you do change them to 23.98 then create a sequence that's 23.98 to edit them in.

 

[Colione]

Thanks for the tips everyone ...

The problem was, I thought I was going to edit at home using FCP, we went to a friends who only had FCE and I figured "since it's written to 60 regardless of what format I film in, it should be ok". I've been informed that those odd interlacing lines is sort of an odd attribute of 24pa. And that when I export I should not see them. I cannot confirm that yet or not, because they just mysteriously stopped appearing. I was trying a million things to get them to go away, nothing worked. I started poking around in other timelines to see if they were messed up or not, and then they stopped!

So thanks for the tips everyone, but it has now been labeled "All Good"



Cole

 

[bgundu]

They will show up again. If you shot 24pA and are editing in a 29.97 timeline, you will have problems in the final output (visually speaking). Yes the tape just thinks it has footage at 29.97 but it accomplishes this by adding redundant frames. Sometimes it hard to see this on progressive monitor like on your Mac monitor. If you captures as regular 29.97 footage, you can still use the Remove Advanced Pulldown in the Tools Menu in FCP after the fact. Otherwise you should have shot this stuff as 24pNormal.