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I’m all googled out from having to try and find a solution for this one, and in the absence of anything resembling a definitive answer, I am posting my findings here for the good of all mankind (well, for those of us that don’t work in NTSC at least…)

And a very big shout-out has to go to Luke Caldwell of Digital Production Factory, who put me on the right track for this in the first place, and is always happy to talk some shop

And also to Carlo Ledesma and the crew of “The Last One”, whose project has been the catalyst for this expedition into Varicam land.

The Varicam is a very sexy camera, but unfortunately if you want to use it with FCP in the 720p25 format off tape, it doesn’t play so nice. Here’s why:

Varicam records 60 frames per second (59.94 in dropframe). Always. It achieves variable frame-rates between 4 and 60fps by ‘flagging’ frames for playback. For example, in the case of 720p25, 25 flagged frames in every 60. If you step through the 60 frames, you’ll see that 25 out of the 60 frames are actually moving frames. Everything that isn’t flagged is a redundant frame (actually a duplicate of the most recent flagged frame). In the case of 24p (23.97fps) or 30p (29.97fps) these redundant frames can be removed during capture (also known as a pulldown).

The image shows the duplicate frames in the source footage before pulldown:

And after:

In the case of 25p, this is only achievable in FCP6 via P2 cards, or a very specific combination of camera (HDX900) and deck (1400A). If you shoot to tape from the HDC27 Varicam, you’re ‘officially’ out of luck.

The Final Cut Studio bundle includes a DVCProHD frame rate converter designed to remove these redundant frames after capture, providing you capture at the full 60 frames per second, and have the deck set to output the frame flags. The downside is that 60fps chews up a lot more space than any other frame rate (double that of it’s closest counterpart, 30fps). If you have the space, though, the FRC allows you to create 23.97, 29.97 or 59.94fps files from your 59.94/60fps source files. Again, sadly, 25fps is not a supported feature here.

Conventional wisdom says that the use of a Kona or BMD card is required for 25p, as they have settings that enable the pulldown during the capture process. A good solution, but going through HD-SDI involves a re-encoding of the video, even if you capture at DVCProHD 720p60. It would be nice to be able to utilise the simplicity of a firewire setup, and keep all the Varicam footage in it’s native codec.

Fortunately, where there’s a will, there’s a way.

By capturing 720p60 via firewire – you have ALL the information. By using the DVCProHD frame rate converter tool in FCP (it’s not installed by default in v5.1, but can be found on the install disk under ‘Extras’, and available from the ‘Tools’ Menu), we can create a pulldown to 24fps.

This takes the 25 flagged frames (when set to “remove duplicate frames”), discards the redundant flagged frames, and plays back what’s left at 24fps. We’re very close, but still a frame off the pace. At this stage I compared my 24fps clip with the original, and the 24fps clip lagged behind, predictably slipping a frame each second.

At this point, we open the new 24fps quicktime movie (with NO redundant frames left in it) in Cinema Tools and conform it to 25fps. This speeds it back up by 1 frame a second, creating a new reference file (or new media if you prefer) that plays very smoothly and also keeps up with the original file! Voila, we have just created a 720p25 clip. Adjust your sequence settings accordingly and you’re cooking.

For off-speed material, again, conventional wisdom indicates that a frame rate converter box is necessary. It’s not a bad idea, but you will lose all timecode references, and it’s an extra piece of kit – we’re trying to keep this simple with a minimum of expense and fuss.

Once again, if we digitise, say, a 15fps clip, brought in via firewire at 59.94/60 (Varicam allows anywhere between 4 and 60 fps) then we run that through the frame-rate converter in FCP once again. Here’s the trick: there are three options in the FRC: 23.97, 29.97, and 59.94. By selecting 59.94 and ticking the ‘remove duplicate frames’ box, the FRC discards the redundant frames, leaving us with only the 15 flagged frames playing back at 60fps – a sped up clip.

You could export this out as a new piece of media @ 25fps which would bring it into line with the rest of your cut. Most workflows suggest working with off-speed material as a separate entity to your 25p footage, so I don’t see this as a big deal.

Also, just like any other film-style workflow, you will have to resync your audio to the clips. This is simply a matter of relaying the audio from your clips against the conformed clips.

The one element here that is sadly lacking is any kind of batch process for the DVCProHD Frame Rate Converter. You need to manually process every clip within FCP. The 24 to 25 conform can be performed in Cinema Tools through a batch, though, so that’s something!

If anyone out there has a solution to the batch processing thing, I’d love to hear it.