premiere 24p "shudder" problem

[dragon]

Hey guys, I'm editing a video shot in 24p on the DVX in Premiere Pro 1.5 and have a weird problem. Most of the footage looks great but a few of the clips play with a weird "shudder" effect. I checked it out frame by frame and the bad clips follow this order: 3 good frames in a row, then 1 bad, shakey, interlaced frame.

Anyone know what the problem might be? I've tried recapturing the footage and it doesn't make any difference.

[Neil Rowe]

use secene detect to capture and only use 24pa with PPRO1.5 to work with 24p. it needs to detect the new cadance for each clip so scene detect will break each shot into its own clip.

[kecorcoran]

Yes, iamloser is correct, it sounds like a pulldown removal problem. As he said, be sure to use scene detection on your capture.

But, I've had the experience where even with scene detection I got this problem. My heads were dirty and the transition between scenes was kind of rough -- when the new scene started, you would still see blocks of data from the previous scene for one frame. This seemed to confuse Premiere pretty badly and I saw the problem Dragon describes. Even repeated attempts at scene-detected capture gave the same result.

In the end, I had to recapture manually, making sure the new in point was a little bit into the scene so none of the confusing garbage data was in the clip.

What Premiere needs is a real "Interpret Footage" command like in After Effects, so we could manually set the pulldown if Premiere gets it wrong.

[Andrew Brinkhaus]

Does Premiere 6.0 require "scene detection" capture for proper 24p timeline editing?

[Sirius_Doggy]

.
http://cakili.image.pbase.com/image/45188596.jpg

[Mino]

Does Premiere 6.0 require "scene detection" capture for proper 24p timeline editing?

Sigh....6.0 wont edit on a 24p timeline you have to go Vegas or prem pro for that magic.

[PimpDaddyDA]

Dude, I'm new here, and have many "start up" problems with PPRO... still learning...BUT... I had the SAME problem as you, and got a lot of technical answers and tons of input, which is really GREAT, I do love this site... but, still no correct answer... but, this one I found on my own....

To get rid of that every 3 frame good, one bad...crap.... (you're gonna die when you here this) Before you capture, go to the settings tab on your capture, look down on the right side to: DV Device Control, click Options...
Then, where it says Timecode Format make sure it says Non Drop-Frame.

Mine was on Drop Frame.... and I had the same problem. NOW, I captured using Non Drop Frame, and presto!! Perfect DVX footage in 24 frame...NO fludder, no interlaced garbage...

I do not use scene detect or nothin... a simple click and I'm back in business.

Let me know if it works for you.

( I want to know if I stumped the pros!! )

[Neil Rowe]

..theres no way around not usining scene detection in PPRO right now for tape capture of 24p. ..unless you capture manually shot by shot. or using batch capture with designated ins and outs per shot. it will pull it all in and assume its 24p. but if you check your footage frame by frame further down the clip your sure to see interlaced frames because ethe cadance will be screweed up. scene detection is a must. without it it will seem to work ok but id bet 99/1 that your footage will be screwed up. :(


you need to use scene detect because even if the whole tape is shot in the same mode like 60i or 24pn or 24pa.. if you using a 24p mode the patten for putting 24p into the 60i stream would be used throughout the tape, but from shot to shot the patten may not have started on the same frame to fall directly in line with the last shots pattern. so if one clip goes 2:3:3:2:2:3:3:2:2:3:3:2:2:3:3:2:2:3:3:2:2:3: and then you stop recording and start up the next shot. it might just start from the beginning again with 2:3:3:2 2:3:3:2 so for each shot the pattern is fine and when using scene detection it will preform pulldown on each clip based of each clips pattern detected, but if you do it all as one clip and the pattern is suppsed to be 2:3:3:2 repeating, and it stops on 2:3 and starts with 2:3:3:2:3 and stops and starts with 2:3:3:2 again.. when PPRO looks at you one big long clip, it only loos at the first few frames to detecte the patern for which to remove the interlaced frames from 24pa and then repeats the pattern through your whole clip, but your pattern will be messed up becuase it is not cosistantly 2:3:3:2 repeating.. so it will start removing the good progressive frames and keeping the junk interlaced ones when the pattern goes off. every now and then a clips pattern on the tape may happen to line back up with the original one and it will work fine for that one shot again.

basically it needs to see the pattern for each clip/shot to remove the interlaced frames and extract the 24p correctly.. the pattern from shot to shot can an will vary over a tape length . and if you make it all one clip it it uses the pattern from the first shot in the clip and runs the same pattern through the whole clip. and yuor other shots will have a screwed up pulldown. SCENE DETETECTION IS IMPERITAVE to getting proper 24p footage.

[PimpDaddyDA]

Instead of running Scene Detection, for the large batches you don't want to break up.... you can simply click "Abort capture on dropped frames" that way you can still run the whole tape, and if you miss one frame (which triggers the faulty cadence ) the machine stops, log the scene, and move on to the rest of the tape. Sometimes you get lucky and there are no dropped frames on a whole tape.... other times, when I get one, it is usually at the beggining or end of a scene... easy to log and keep on truckin....

[Sirius_Doggy]

Pimp - It has nothing to do with dropped frames. It has to do with the 2:3:3:2 pulldown and it will not work properly unless you use scene detect.

[PimpDaddyDA]

Well, yes and no... I noticed that I'm getting the same results w/the dropped frame box on, or the Non drop frame box on.... (what is that for anyway? )

BUT... the scene select is a tool for dividing scenes into files, the problem is when a frame is dropped or missing from the next scene, the order (as you say ) goes out of wack. the 2/3/3/2 order will get messed up for the next scene.... when I have it on "abort capture on dropped frames" the system acts like a scene detect for missing frames. It stops the capture. I then restart it where it left off, and now the next scene's footage is perfect. Maybe I'm explaining it wrong cause I'm new to this kind of stuff.. but I'm getting the results I need. Clean transfer without scene detect. Only about 1 or 2 frames lost per hour of footage in the begining or ending of a scene.

I know I may be wrong... but what the hell.... if it works, I won't fix it.

what is that Timecode Format selection for anyway? I can't find it in any book or online tutorial? DV device capture / non Drop frame or drop frame choice???


Thanks,

Darryl

[Daygola814]

I have a question... If I capture 24pa footage take by take, making sure that I do not capture any video from the take before or after.... will premiere screw up cadence? Also, I was thinking about taking my footage with 2:3 pulldown, importing it into Vegas, then exporting it as an .avi inserting 2:3:3:2 pulldown so that I can take that file and import it into Premiere. Will this cause any noticeable degredation of the image? I'll be rendering this footage back out to DVD using mpg2 compression. Strange, I know. I shot 1/2 my film 24PN before I knew anything about 24p. Now I want to finish the 2nd half of it with 24pa because of better compression and the fact that I want to edit in a 24p timeline. I own both Premiere and Vegas but I like editing in Premiere better cuz I can edit faster.
Ya'll probably think I'm crazy now.... haha
Thanks!
Paul DV

[Neil Rowe]

should work fine. but PPRO 1.5+ can do the pulldown on 24pn footage too.

[Daygola814]

It can? Since when? And how(is there a trick to it?)? That's the main reason I switched to Vegas! I have 1.5... When did they fix the bug? Wow.. I'm out of the loop...
-Paul DV

[Sirius_Doggy]

what is that Timecode Format selection for anyway? I can't find it in any book or online tutorial? DV device capture / non Drop frame or drop frame choice???

Pimp - The difference between drop frame and non- drop frame is about 18 frames every 10 minutes.
You see - video is not really recorded at 30 frames per second. It's recorded at 29.97 frames per soecond.
On a non drop-frame system like most consumer camcorders that small difference would add about 18 frames every 10 minutes.
On a drop frame system the timecode automatically "drops" two frames every minute except when the minute is divisible by 10 - 10minute mark, 20minute mark, etc...
HERE is an article that explains it in more detail. (http://www.andrewduncan.ws/Timecodes/Timecodes.html)

So if you're shooting home movies it really doesn't matter what method you use but if you are shooting something for broadcast on a local television station, you'll want to use drop-frame. A 30 minute program could be off by as much as 1.5 seconds on timing on a non-drop-frame count.

One other point - It's not actually dropping 2 frames of video - It's ONLY changing the TC counter.

[Barry_Green]

That last sentence is key: the difference between drop-frame and non-dropframe has nothing to do with the video itself. The video is identical in both cases. The difference between DF and NDF is how the frames are counted, not the frames themselves.

NDF numbers each and every frame individually, sequentially. The result is frame-accurate, but is not an accurate judgement of the actual running time (because, as Sirius said, the frames are numbered at the rate of 30 frames per second, but the video actually runs at 29.97 frames per second, so there's a discrepancy between reported runtime and actual runtime).

DF adjusts the timecode so that it accurately reflects the running time of the program. It skips a few frame numbers here and there to keep pace with the running time of the video.