Interlaced video coming from 24p source

P

prohtex

New member
Hi and sorry if this question has been answered elsewhere. I've done quite a bit of reading though and I'm still in the dark on this one. I have a DVX100B and almost always shoot in 30P. I hate interlaced frames and never use a CRT to view anything. I don't even usually edit in FCP, but I always use it to capture. I have no interest in "film look." All I'm interested in is getting a quicktime file with 30 distinct images for every 1 second.

So that said I have a custom capture profile that usually works well in FCP5. (I have 5.1 as of recently but I don't think anything major changed) In my profile I checked "Progressive" in the advanced box of the quicktime compression dialog. When I shoot 30p I always get a quicktime file without interlacing. (To see if a quicktime movie is really interlaced you have to check "Use high quality video setting when available" in the Quicktime Player prefs). So I'm usually happy.

I recently shot something in 24P by accident. (There is a possibility I shot in 24P Adv but I am almost sure I didn't) Oops. I CANNOT for the life of me get a quicktime movie with distinct frames. Every capture preset I try results in some combination of interlaced and noninterlaced frames. Again I don't edit in FCP and my only goal here is to get the video into some format where there is no interlacing whatsoever.

I read all the tutorials on 24P including the Barry Green DVX book and the Nattress guide, so I understand that the video is 24 distinct frames in a 60i wrapper. When I preview the video in the FCP log and capture window, I can use the software controls to advance the MiniDV tape 1 frame at a time in the DVX, and I see that there are 3 clean frames followed by 2 interlaced frames in sequence (I don't know if this proves that I shot in Adv or not). But everything I am reading says FCP is designed to extract the true 24p video from the camera WITHOUT recompressing / processing (in other words dynamically on capture). I have tried just about every "Easy Setup" and many combinations of custom settings. Basically I am sitting here capturing short clips over and over again.

Again to be clear I'm not necessarily opposed to processing this video a bit to get back to true progressive frames. It would be a bummer but I don't care bc I usually don't shoot this way. But I can't believe everything I try results in interlaced quicktime movies in the Capture Scratch folder. Any help is appreciated. I'm also curious if there is a menu setting on the DVX to show what mode a video being played back was originally shot in.

Since everything I'm reading says "if you shoot in regular 24P just capture as normal and everything will be fine" naturally this is confusing.
 
If it's 24P then you need to use Cinema Tools to Reverse Telecine (remove pulldown) from clips that were captured at NTSC normal (29.97) These will go through a de-interlace/reinterlace and re-compression for the changed frames.

If it was 24PA then FCP will remove the pulldown on the fly using Advanced Pulldown Removal.
 
Thanks I was just about to post that I found this answer here:

http://www.larryjordan.biz/articles/lj_dvx_capture.html

For 24p standard you still capture at 29.97. Then if you wish to conform the captured footage to true 24p you do this in CinemaTools, according to the manual. That's why 24pA was designed because it can be conformed automatically by FCP. 24p standard requires more work.

Does anybody have an easy step-by-step for this? If not I guess I'll just dive in...
 
I guess I must have shot in 24p (not Adv). So how do they do 30P without a wrapper? Because isn't it really 29.97? Are there repeated frames or something.

I had heard before that you can "safely" use normal 24P mode unless you want to print to film (which I don't want to do). I guess that is a bit misleading -- you also have to use it if you want an easy way to get real distinct frames without recompressing.
 
PS. For those interested I just did it and its a relatively simple process. Instructions follow.

Instructions for getting real progressive video from footage shot in 24P mode:

1. Capture using the de-facto FCP capture settings. You can do this by choosing the "DV-NTSC" Easy Setup and Log and Capture. This will capture at 29.97. Not to worry.

2. Run Cinema Tools and choose File->Batch Reverse Telecine. It will ask you to choose one file in the folder that all the files are located in. Go make a sandwich.

3. Presto! Solid frames at last. Not quite as clean as 30P but not bad.
 
One of the main reasons for 24fps is to simulate the motion of real film.
As far as which process to use:
24p in 29.97 timeline is the easiest and allows you to go to tape or DVD
24p with pulldown removal (in Cinema Tools) is useful IF you want to go film, 24 fps DVD or the web.
Note that pure frames are only useful in these purposes. If you want to end up with a video tape to play the it has to have itnerlacing.
If your target really is pure 24 frames in a 23.98 sequence then you shoudl shoot 24pa mode. This saves additional steps and disk space from having to do pulldown removal after capture. It also provides slightly higher quality.
 
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