Premiere recognizing 30pN footage as interlaced

Gregg A. George

New member
I recently shot some footage on my HPX-170 in DVCPROHD 720/30pN. Upon importing to Premiere CS5, the footage appears interlaced during playback. Project/Sequence is 720/60p preset with timebase set to 29.97. When exporting to H.264 HD quality mp4 the interlacing is still there so its not just playback problem inside premiere.

I can solve this by interpreting the footage as interlaced (lower first) within premiere, then exporting as progressive 29.97- but I know the footage captured is 30pN. Why would telling Premiere to interpret 720/30pN DVCPROHD footage as interlaced correct this problem?

I know I was recording in 30p Native, as the recording time would have been halved if it was 30p (over 60).

I feel weird telling Premiere to interpret footage as interlaced that I know is progressive-but it's the only thing that will make the footage look right.

Any ideas what's going on here?
 
Yes, I used the DVCPRO HD 60p preset and merely changed the timebase to 29.97. Very weird...right now I am consciously telling Premiere to interpret footage as interlaced that I know is progressive.

If it was actually recorded in 720/30p over 60, (which I am pretty sure it wasn't) would Premiere then interpret it as interlaced being that it is delivered in a 60i stream?
 
Premiere is normally pretty good at getting clip settings correctly. Drag your clip to the "new sequence" icon and it will create a sequence based on your clip's settings. If it's still interlaced, then the clip is interlaced and that's how it was recorded.

The sequence presets really don't mean anything to be honest. If Premiere detects your clip as interlaced, it's interlaced.
 
It's not possible for 30pN to be interlaced, because 720p is never interlaced.

A bit later, I will try to replicate the problem.
 
Thanks, guys.

When I use a default 720/60p DVCPROHD sequence, the footage looks and exports fine, though the frames are doubled in the timeline.

The problem occurs when I change the timebase from 59.97 to 29.97. Then the footage appears to be interlaced and exports the same. It is only corrected by conforming to lower fields first.

I am positive this is Native 30p footage, can't understand why changing the timebase would cause this?

On another note - for some reason I am unable to drag a clip to the new item icon to create a new sequence.
 
You're certain that all you change is the frame rate?

Probably not the issue, but try changing the timecode to Frames instead of 59.94.
 
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