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Varicam 23.98 Conform to 60p – 2 Questions
Hello, everybody!
I am currently setting up to deliver a 50 min show shot 24p (23.98) Varicam, outputting to a D-5 at 720p 59.94 Drop Frame Timecode.
the entire show was cut in a 720p 23.98 DVCProHD sequence – now we’re exploring our output options.
Normally we’d just let the decklink card add a 3:2 pulldown on the way out but a handful of additional deliverable materials (paper-cut, EDL, OMF and annotated shot lists) need to be created and delivered with Matching timecode to that of the tape. Obviously, it’s going to be much more efficient to step through a timeline then a tape to get this info, so my questions are these;
QUESTION 1
Is there any reason NOT to trust FCP 6 (which seems can add a proper 3:2 cadence to 24p footage by dropping it into a 60p timeline) to give us accurate ins? (I understand that clip out points may be off by a frame or two due to the pulldown) We will not be outputting from this 60p sequence but only using it as reference for the paperwork.QUESTION 2
If I export a 24p self-contained quicktime and bring it back into a 60p sequence – it seems that a proper 3;2 pulldown is added, so is there any reason NOT to use this for our output to 720p 60 tape?
(the reason for this is to be able to add a few shots of 29.97p stock footage and title sequences without having to do any intrusive frame rate conversions)If my calculations are correct, the answers to both questions is ‘no’ but post-production consistently shows me that the theory is rarely the same as the practice.
Please let me know if I can be more clear on anything – if anyone has had problems/successes with this or similar work flows I’d appreciate hearing your experiences.
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4 Replies
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Question #1: Sounds like a bad idea, as far as making an accurate EDL that, sounds like a not good idea. For Question #2, I am doing that for our current show and it works out fine. We work in 23.976 Pro Res sequence, but lay off 59.94 manually cutting in betacam stock footage and DV footage to preserve their framerates fluidity. We’re about three episodes in, and all have passed tech eval fine.
Richard Sanchez
North Hollywood, CA“We are the facilitators of our own creative evolution.” – Bill Hicks
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When dropping 24p into a 60i sequence in FCP, it is not good. It doesn’t add 3:2 pulldown, it adds 2:2:2:4, which is unsuitable for broadcast IMO.
I haven’t tried doing 24p into a 60p sequence. You say it does add 3:2. If you can confirm this, then there’s no reason to not go ahead with it. Just make sure it is 3:2 and not 2:2:2:4.
As far as EDL. Your media’s source timecode should already be 29.97. Even when you capture 23.98 from a Varicam, the media retains the 29.97 formatting even though the actual video is 23.98. The only time the timecode gets changed to 23.98 formatting is if you use Cinema Tools or Compressor to do a reverse telecine. Or the DVCProHD frame converter.
If your TC is 23.98 formatting, then you can change it back to non-drop 29.97 by using Final Cut’s “Modify->Timecode.” This won’t affect the edits in any of your sequences.
Sean
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Yes, you’re correct about a 2:2:2:4 pulldown when going from 24p to 60i. When I drop 24 into 60p there is clearly a 3:2 cadence. My understanding is this; since FCP operates in frame-based editing (not field based) it does us the “favor” of keeping field issues out of the equation and using a 2:2:2:4 cadence which IS essentially un-acceptable for most (or all IMO) mastering standards.
However – these limits are gone when we’re dealing in 60p because each frame of 24p can be assigned to it’s own dedicated full frame (not any fields) in a 3:2 pattern without excessive rendering and editing in a base 60 rather then 30 there are none of those “untouchable” single field flash frames as result. When stepping through, there is clearly a 3:2 count throughout.
The problem we are finding is that if we were to copy paste the contents of our edited sequence- some clips are a frame short… meaning that at some edits there ends up being a 1 frame hole in the timeline: I understand that this to be because the XML data for a sequence holds each clip’s source ‘in’ TC and ‘out; TC but only the timeline’s ‘in’ TC (not the “program” ‘out’) therefore, for the purposes of just making annotations (for footage licensing purposes) on paper with refrence to the final tape’s timecode should be reliable within a frame or two (which is good enough).
Basically, as I research I’m finding that dropping a self-contained 24p Quicktime into a 60p sequence will be accurate and suitable for output for any standard broadcast purposes – so if there’s not any drifting, slipping or other time accuracy issues with this, I SHOULD then be able to rely on the TC in the sequence as an accurate (within a frame or two) representation of what will be on tape (provided that there are no other issues) … my logic is telling me this is true – I’m looking for that thing that one thing behind the scenes that is going to screw up our delivery.
If there are no issues, this will actually open up some fantastic versatility and workflow options with the Varicam format/FCP for us that thus far I haven’t heard of anybody championing so I’m cautiously optimistic.
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That’s interesting, because certainly I’ve heard all the horror stories of putting 24p material in a 29.97 timeline which made me apprehensive at first with the show I’m working on now, but it worked out fine (being 720p 59.94) and I haven’t noticed any issues with it, and certainly neither has the network.
Richard Sanchez
North Hollywood, CA“We are the facilitators of our own creative evolution.” – Bill Hicks
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