[This article was first published in the July, 2010, issue of
Larry’s Final Cut Pro Newsletter. Click here to subscribe.]
Matt Cohn asks:
I am assisting on a project that is dealing with three different formats: XDCAM EX, DVCPRO50, and archival material ripped from DVDs. Before getting into the specifics, I want to let you know that the project needs to be delivered for broadcast in ProRes at 29.97. Now for the workflow question.
We have decided that it would best to edit in a sequence setting of XDCAM EX to match the XDCAM footage, so we need to figure out the best way to convert the DVCPRO50 footage. I read in one of your past exchanges that you recommended using ProRes 422. Would this make sense in our situation? During that conversion we are likewise planning on converting the frame rate from 29.97 to 23.98. Can this also be done with the ProRes 422 codec?
The goal is to be able to match the two formats that are not XDCAM EX to that format using the best codecs possible and, finally, for output, we would then go from the XDCAM EX codec to ProRes at 29.97, but only after color correcting and audio mixing.
Larry replies: Matt, thanks for writing!
You have three issues:
First, depending upon your budget, you can up-res using Compressor or I’ve seen outstanding work with tools from the Foundry – called Furnace Core – that can do the job, or you can take your footage to a post house who can use a Teranex box to do a hardware up-conversion.
Second, I have NO idea why you want to do a frame rate conversion from 29.97 to 23.98 only to go back to 29.97 for final delivery. This will make your footage look jerky and awful. If your XDCAM material was shot at 23.98, convert it to 29.97 for smoother movement. This double-frame-rate-conversion step is unnecessary and decreases quality and wastes time.
Third, I like ProRes 422 for a common codec. For broadcast you can use either ProRes 422 or ProRes 422 HQ.
Matt then asked:
I have a couple of follow up questions that I hope you have time to address. If we were to edit the DVCPRO50 NTSC 29.97 footage on an XDCAM EX 1080p24 timeline – the majority of our footage is XDCAM at 23.98 – when it comes time to output to say ProRes 422 at 29.97, how are the two different frame rates addressed? In other words, am I correct in assuming that the XDCAM frame rate and the DVCPRO frame rate have to match before output to the ProRes codec?
Second, if I understand correctly, and if we were to keep all footage in their native codecs during editing, in an XDCAM EX 1080p24 sequence that plays DVCPRO50 footage in real time, is it actually converting the 29.97 frame rate during playback to 23.98. or is it playing back at 29.97 from the 23.98 timeline?
Finally, I wasn’t sure if you meant to convert XDCAM footage, which was shot in 23.98, to 29.97 before editing, or once the edit was finished and we were ready for output.
Larry replies: You can only have one frame rate per timeline. This means that you need to either remove frames from the DVCPRO-50 material, which will look awful, or add pull-down frames to the XDCAM EX material, which will look better than trying to remove frames.
This frame rate conversion can be done automatically by Final Cut Pro in the Timeline, or you can do it before you even bring the material in for editing using Compressor (to add frames) or Cinema Tools (to remove frames).
If you edit DVCPRO-509 material into an XDCAM timeline, Final Cut will automatically render it into the correct image size, codec, and frame rate. This means you’ll need to render every SD clip you edit into your project. Whether the quality of this automatic process is acceptable to you is up to you to decide.
I would suggest converting all footage into a single ProRes codec – I recommend ProRes 422 – at a single frame size, frame rate, and scanning (progressive) – so that you are editing only one format on your timeline.
Then, when the project is done, export a high-quality self-contained QuickTime movie and down-convert it to SD using Compressor for final distribution on DVD.
