Interlacing/pulldown issues on the DVX-100B

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DreamingAwake

New member
Let me just start by saying I've read through just about every article/forum posting on the subjects of deinterlacing and pulldown I can find. Even after looking at everything, I still continue to have problems (so I must be some kind of moron).

My issue is basically this. I've been shooting a project on the DVX-100B in 24fps (not 24A, mind you). When I capture the footage in Adobe Premiere CS5 either into a normal DV NTSC (29.37) project or into a 24p (23.97) I get interlacing artifacts (or what I thought were interlacing artifacts). I read about pulldown, and how the camera is actually shooting in 29.37 rather than true 24p and how I need to remove the pulldown to get the 24fps I'm trying to get. When I capture the footage into a 24p timeline in Premiere it removes the pulldown, but my footage still contains the same interlacing style of artifacts I had before about half of the time (I have no idea why footage shot with the same settings would behave differently in the same project... But it appears to, and this is what has thrown me a complete curve ball).

So I'm at a complete loss here as to how to capture my footage, how to edit it, and how to render it. I never had any problems in the past... I would simply drop my footage into a 24p timeline in Premiere, edit, render out as progressive with no interlacing. Done, perfect for viewing on the computer/web (which is my ultimate destination with this project for now).

So, let's just go completely all the way back to step one. Apparently I have no idea what I'm doing, so can someone PLEASE walk me through the process of capturing, editing, and rendering for 24p footage in Adobe Premiere? I've tried everything I can think of.

Thanks in advance for taking the time!
 
You said you were not shooting 24P Advanced....I think that's where the issues come from.

Shoot 24P advanced as that is the one meant for extracting pure 24P from the 60i. The other 24p is for when you want to get the look of 24P but edit it just like standard video at the standard video frame rate 29.97.
Make sure to check the proper advanced pulldown 2:3:3:2. This is coming from Adam Wilt BTW.
Now it actually makes sense to me as well.
Hope this helps you out.
 
Hey Pulp, thanks for taking the time to reply. In the future, it sounds like shooting 24PA is the way to go, but I have a ton of footage for this project already shot in 24P. So what is the best way to get the best results with 24P footage? From Capturing, to editing, to finally rendering? Back when I started filming the project, I read Green's "The DVX Book" and if I remember correctly it says that if you are planning to not transfer your footage to DVD you should shoot in 24P as opposed to 24PA. So I think that's why I initially started shooting in it. Anyway, how do I handle the footage I have at this point?
 
DreamingAwake said:
When I capture the footage in Adobe Premiere CS5 either into a normal DV NTSC (29.37) project or into a 24p (23.97) I get interlacing artifacts (or what I thought were interlacing artifacts).
Click to expand...

First, you need to straighten out your frame rates. It's 29.97 and 23.976 (aka 23.98).

Now, you've read up on how the camera records with a pull-down. 24pA is the better choice for editing at 24p (23.976), just because the 2:3:3:2 pull-down is easier to remove and does not require re-compressing any frames of video. (If you haven't read Adam Wilt's explanation on the difference between 24p and 24pA, you should.) That said, CS5 should be able to auto-detect both 24p and 24pA, and remove the pull-down automatically. If you're having the problem only part of the time, it sounds like an issue with CS5, and perhaps you'd get better answers in the Premiere forum.
 
I don't know if it still holds true, but in an old thread from right here, it says to always capture DVX footage @ 29.97....but the pulldown required for 24p standard is 3:2 rather than 2:3:3:2 for advanced. Do you have options for the different processes of pulldown- Premiere Elements has both, so I would think that CS5 would have both as well.
 
To be clear:

When the DVX shoots 24p, it shoots 23.976 whether it's in 24p mode or 24pA. It also records both of them to tape in 29.97 (actually 59.94i). The only difference is how the pulldown fields are arranged. Again: both are imaged at 23.976. Both are recorded as 29.97. The only difference is the arrangement of fields.

In PP, you have no choice as to how you capture -- it's always captured as-is from tape, so the AVI files are 29.97. Pulldown is removed automatically when dropped into a 24p sequence whether it's 24p standard or 24pA. There are no boxes to check or to set.

As for when to shoot which, only shoot 24p standard if you absolutely cannot edit on a 23.976 timeline and MUST edit on a 29.97 timeline. Otherwise, shoot 24pA and edit on a 24p timeline. What you plan to do with it -- DVD, broadcast, transfer to film, anything else, doesn't factor into the decision as to what to shoot. Only how you must edit. (Disclaimer: if you mess up and shoot 24p standard when you meant to shoot 24pA, in PP, you're still OK. You're OK in most other NLEs, too; it's FCP where you really have to watch.)
 
C2V - Sorry about the 29.37 statement. It was a typo on my part. I looked through Adam Wilt's article in the process of trying to figure this whole issue out, but apparently I didn't read it thoroughly enough. I'll read through it again. I sincerely hope it isn't an issue with CS5 not detecting the footage correctly... When I make a 24P project in premiere to capture/edit it specifically says in the settings the following:

For editing 23.976 fps footage shot in 24P or 24PA (24P Advanced) modes.
Standard NTSC frame aspect ratio (4:3).
48kHz (16 bit) audio.
2:3:3:2 pull-up for playback to a DV device.
Fields: No Fields (Progressive Scan)

It detects the footage as 24P and applies pulldown to it automatically. It lists the frame rate by the footage as 23.976 fps but it also automatically defaults to using the field order from the footage (which it detects as lower first). If I change this to progressive, it has no effect on the footage.

If I drop my footage into a 29.97fps timeline, I have to render the entire work area immediately because it lists the footage as being 23.976fps. I still see interlacing in the video sequence monitor, but this can be removed by viewing only one field for editing purposes. When I render the footage out later at 29.97fps (if I change the setting to 23.976 it messes everything up obviously), I end up with an interlaced file if I leave the interlacing as lower field first. Or, if I choose progressive, then the interlacing appears to be basically gone except a new problem appears.... I end up with semi jagged edges on subjects/objects in my footage (it looks like an aliasing issue or something). This problem is not present with the footage is rendered as interlaced, but obviously the interlacing issues still are.

Pulp - When I capture my footage, I don't get different options for pulldown as far as I know. The only option to turn pulldown off or on comes later on after I've captured my footage. If I go to my footage and select modify > interpret footage, I get the option to "Remove 24p DV pulldown" in checkbox form. That is my only choice for removing pulldown that I know of. Of course, if I am capturing/editing in a 23.976fps timeline, Premiere automatically turns the pulldown removal on because it detects that my footage is 24P.

So, I'm still really not sure what to do about all of this, but I feel like we might be making progress. Also, sorry for such a lengthy reply, guys. I'm trying to be very thorough and not leave any info out.
 
Thanks for clearing that up, David. That answers a bunch of my questions. I'm still not sure what to do about my apparent interlacing/pulldown issues though. So, I understand that premiere will simply capture the footage as is. And then I drop it into a 29.97 timeline because that is what 24p was meant to be edited in? And if so, this results in jagged aliasing issues that look different from normal deinterlacing artifacts and that disappear if I remove a field from the footage. Ugh, so confused on what to do. It seems like no matter which timeline I put it in, or how I render the footage out in the end, there is some sort of nasty issue with the picture.
 
I think David says that it will capture automatically at 29.97. Then when you drop it into your 24P timeline it's supposed to automatically remove the pulldown.
 
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There is no "remove pulldown" option; it just does it automatically when the clips are in a 24p sequence.

DreamingAwake, you should be able to drop it into a 24p sequence and pulldown should be removed. I tested CS5 thoroughly on this point about a year ago, and it worked fine when I did. You should be able to simply capture and drop.

Start a new project, open a new 24p sequence, import the footage you captured, and see if it removes the pulldown there.

"Aliasing" may be something different. Did you shoot with THIN Vert. Freguency Detail?
 
David - When I drop the footage into a 24P sequence, it does remove the pulldown.... Some of the time. The rest of the time the interlacing artifacts are still present. In fact, it can happen in a piece of footage from the same clip. It appears to work fine, and then when a take ends and the next one starts up there will be interlacing issues. So, the problem seems to be intermittent. As far as the aliasing, yeah I did shoot with THIN vert. Frequency... I'm guessing that much like shooting in 24p, that was also the wrong move, eh? *sigh*
 
It sounds like you may be capturing without scene detection enabled, so instead of getting separate clips whenever the camera was stopped and started, you're getting a long continuous clip. This could well be the problem, because from the end of one take to the start of the next take, the pulldown cadence might be disrupted. The pattern might be something like 2:3:2:3:2:3:2:2:3:2:3:2:3, when it's expecting a continuous 2:3:2:3 . . . .

So, it'll throw off pulldown removal.

As for THIN, it makes the vertical detail the highest it can be, which is a little higher than a standard TV can display without flicker. It's also a little higher than standard DV, so you sometimes see a stair-stepping of diagonals.

THIN is best used when you're planning to uprez the footage to something higher; it preserves as much detail as possible. THICK will assure that you won't get flicker on a TV, but the vertical detail won't be as high. MID is, well, mid.

You may not see a problem in your final render at all -- but if you do, it's nothing that a tiny vertical blur won't solve.
 
Thank you very much, David. I went back and looked at the capturing setup I used and you're right. Scene detection was not enabled. I'll go back and recapture everything with scene detection turned on and that will hopefully solve the issue of the disrupted pull down cadence. In the future, I'll also probably shoot in 24PA since it sounds like a better option for what I want to do. I'll also shoot with MID or THICK vertical detail from now on. Unless it's worth uprezing the footage and unless someone wants to try to explain the process to me (since I know essentially nothing about what is involved). Anyway, thanks so much for all the info, I've learned a lot. The only thing I'm wondering is, is it worth shooting in 24PA from now on for this same project? Or will dropping 24P and 24PA into the same timeline in Premiere cause more problems than it's worth?
 
Hi, first time posting.

First of all, premiere shouldn't ask you to render if the sequence settings match the footage properties.

Create the 24p dv sequence, put some material in it.
Red bar? then try a 29.97 sequence. Red bar?

I dont think the capture settings affect the captured footage, premiere autodetects if you shot on 24p, but not 100% shure.


On the other hand I think you problem is in your chosen monitoring settings, premiere does not deinterlace footage in your monitor (program window).

Try monitoring trhough your DV camera or deck...

How does it look?

Now, for premiere right click on the program window (monitor)... on the fields option, does it have "display both fields" selected? there's your problem. Select "display first field"

That should do it.... you might also want to try playing with the "frame blending" option right clicking on the video edit in the timeline.

hope I was right, hehehe

Let me kwow.

Saludos from LA (That's Latin America :)
 
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