24p + 30p in one project
 

Let's pretend that I've got an HD project that is being shot in 720p. Let's also pretend that I don't want to commit to one frame rate or the other in that I'd like to have the majority of the project be 30p with select elements having the film cadence of 24p. Is this possible in one 720p timeline? Were it an interlaced format like 1080i I know I could do a 3:2 pulldown on the 24p footage and it would fit perfectly, but I'm working in a progressive environment. Do I have any options here? It seems that just dropping in a 24p segment and rendering doesn’t look TOO bad, but it’s not perfect. Thanks for your help.

Shooting 50i and 60i is easy to go to 24p. 30p, however, is darn near impossible and VERY expensive to transfer to 24p. I recommend shooting in 24p and you can easily showcase it because TVs and DVD players support 24p.

heath

I agree it would be best to do 24p throughout, but due to the subtle differences between 24p and 30p I'd like some sections of the project to have the realistic "video" feel, and other sections to look more like film.

Based on what I've found there is no way to get 24p into a true 30p timeline (please correct me if I'm wrong). So the way I see it I have two options:

1.) Uprez the 720p footage to 1080i and do a 3:2 pulldown on the 24p footage, leaving the 30p footage as-is after uprez. This would work nicely, but has multiple extra steps in preparing the footage.

OR

2.) Section the DVD to different tracks which link to each other. Say I start out on a true 24p track, then at the end of that link to a 30p/60i encoded track, and maybe back again. The only problem with this is that there would a noticeable pause at the switch most likely. Can anyone think of another reason I wouldn't want to do it this way? To me it seems the easiest in terms of workflow.

Here's a question: What about a 60p timeline? Wouldn't the 24p and 30p footage fit equally well in such an environment? Probably wouldn't work to down-rez to a SD DVD from there, but it's food for thought once that part is cut out of the delivery method.

It's tough to mix formats like 24p and 30p. One of the things every filmmaker and videographer needs to know is what's the final output. If it's HDV 720p24, you may want to acquire, edit and output your video like that.

But if you mix footage, esp. DV or different framerates, you're going to have to convert something and decide what your final output will be.

hwm

Final output (for now) will be an SD DVD at 30p (60i). Like I said most of the project will be 30p, but it would be nice if I could get some film-style 24p footage in there. I guess I should have mentioned by now I'm shooting mainly with a JVC HD-100 which offers the choice b/w 30p and 24p only for HD.

It seems that until 60p becomes the standard for delivery, I'm going to have to resort to converting to an interlaced format (1080i) in order to accomplish what I'm looking for. In any case I'll do some tests before I commit to shooting it. Thanks for your help.

Hmmm. What's the project exactly?

h

Also, what's your NLE, platform?

hwm

The project will actually be a higher end wedding video, but I’m interested about being able to do this on any HD project. For the purpose of the wedding video, I could implement the idea I had earlier to do a multiple track DVD and have the 24p track link to the 30p track when it ends and visa versa since there might be whole sections where it’d be one or the other.

As a whole it would be simplest to stick with all one frame rate, but I’d like to know my options. I try to make all my productions as high quality as possible and like being able to achieve different looks at different times.

BTW I’m using FCP5 on a Mac.

Now why the heck would you want a wedding video to have both 24p and 30p? What purpose do you have for this look?

Anyways the best way to mix 24p and 30p video would really be to convert both to 60p and edit in a 60p project. You will have to take great care where you place your edits so you do not splice the edits on the wrong duplicate frames. When you someday make a HD-DVD or Blu-ray disk at 1280x720x60p you should have a whole sequence that contains both 24p material and 30p material. Again the cuts have to be placed just right so the pulldown pattern doesn't get messed up.

This really does seems like a waste of time having to convert 30p and 24p to 60p. 30p becomes 60p with every other frame a duplicate. 24p becomes 60p by 3:2 frame duplicates.

The other really silly way to do it would be to convert all video to 120p and edit in a 120p project. (can this even be done?) When you are finished you can convert back by taking only every 4th duplicate frame. The 30p should look ok but the 24p might get a little jittery depending on how you choose to pull the frames out. I have never really tried this because it is kind of stupid but it might work.

How about this idea. Your clients may not be able to tell like a seasoned pro would so... for the 'film cadence parts', take the 30P, apply a slight motion blur and perhaps an old film look preset. If you're trying to do a flashback to old home movies type thing, this method would probably sell it.

-gb-

I don't really expect people to understand why I'd take such great pains on a wedding video. But it's my media and I go for what I think looks best.

Also it is an interest of mine for any project, as I said earlier. What would you do if you were making a documentary in 720p30 and you got your hands on some film footage or anything shot at 24p? Are you SOL? It seems to me that you either need to up-convert to 1080i or 60p. Which then calls into question the usability of the 30p format as a whole. I think it looks nice and is sometimes more pleasing than true 60p footage, but as far as flexibility, it won’t take just any kind of footage.

I’m not bashing 720p, though. I would still rather record in 720p than 1080i because I prefer whole frames and interlacing is a thing of the past (once again my media and my opinion). One just needs to take into consideration the flexibility of the format as I am now realizing.

As far as them not being able to tell the difference, there may be something to that. At the same time I’ve learned that respecting your audience goes a long way to making better media. So while I don’t think that they would be able to put their finger on it and spell out the difference, it might be that subtle feeling that it gives which makes it more pleasing and interesting to watch.

It also comes down to the TV you use to watch it. I myself can’t always tell a huge difference between 30p and 24p on a progressive display like an LCD. But any kind of CRT or even probably a 1080i display would show a significant difference because of the 3:2 pulldown put on 24fps footage.

So I may yet decide to shoot all 30p and leave it at that (as it is still quite good-looking). I’ll have to do some testing and decide for myself whether or not it’s something I want to do. As for documentaries and the like, I guess the moral of the story is pray you don’t have to mix footage.

No problem there. Those would be shot in 60i and any old film footage would be telecined to 60i and then included in the sequence.

What you're trying to do is slightly different. Why don't you at least try the method I suggested to see how good you can make it work through your own experimentation. I was only giving you general guidance, the final tweaks are up to you since you are the one editing and viewing the sequence as a whole.

-gb-

I was implying that one would be shooting a documentary with the HD100 or any HD camera where your choices are 30p or 24p. The HD100 only does interlacing in SD formats which is fine if you don't want an HD master. There are also plenty of documentaries shot on film, so don't be too hasty in your assertion that they would be 60i. It depends on the film-maker.

Thank you for your suggestion and I will try it out. The motion blur could look similar to a 1/48 shutter rather than a 1/60 and thus look more filmic. But I’m not going for the old movie look. I'm looking for the nice, smooth, story-like quality of 24p which sets the events portrayed in a look that is slightly outside reality. -Slightly closer to an artistic rendering rather than just an ordinary video. You know what I mean.

Anyway thanks for the advice. I’ll let you know what I find out.

You can add pulldown to the 24p video and turn it into 30i. You then just edit the 30i and 30p video together. When you make a DVD make it as a normal 30i(60i). You might not get a progressive look on digital displays but it would be a perfect mix of 24p and 30p material.

Hi Chad,

There is a very simple solution to your situation, and I think someone may have answered it already.

If I remember correctly, you are a FCP5 user? Therefore, you are going to be using an app like HDVxDV or DVHSCap to capture m2t streams of your 720P24 media. Right?
Those streams are already actually 720P60, the 24frames are layed in a 2:3 pattern. So just batch convert with MPEGstreamclip to AIC at 60fps.
You should then capture your 720P30 media exactly the same way, since the streams are also 720P60 with the 30 frames in a 2:2 pattern.

Therefore you will have camera native resolution in camera native pulldown, all at 720P60. Just edit in 720P60 AIC. (Use the 720P30 AIC preset and just change the frame rate to 59.94fps)

720P60 will downconvert very easily to NTSC for your DVD, maintaining the intended temporal frame rates, and you will have the archive for future formats like HD-DVD or Blu-ray.