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Old November 14th, 2007, 07:38 AM   #1
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conforming 30p

I've shot a video in 720/30p, conformed it to 23.98, then put it on a 29.97 timeline in Final Cut. I pitched the track for playback by 25% during the shoot, but seems like the footage is still out of sync after a couple of seconds. Is my sequence setting correct with 29.97 fps? The end product is DigiBeta.
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Old November 14th, 2007, 10:06 AM   #2
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When you overcrank at 30P for 24P playback you need to run the music track at 125% speed (faster.) I assume this is what you mean by pitching the track by 25%.

29.97 ÷ 23.976 = 1.25 or 125%

Even if the end product is Dbeta NTSC, you should edit in a 23.98 fps progressive sequence until the video is finished/approved, and then output directly to Dbeta and let your card (decklink or Kona) automatically add the correct pulldown and downconvert for you.

I suspect your sync issues are coming from editing 23.98 footage into a 29.97 PROGRESSIVE sequence in FCP. FCP adds a simple pulldown, but if the sequence is set to progressive then it doesn't handle 2:3 in fields properly because it is supposed to maintain full frames.
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Old November 14th, 2007, 10:22 AM   #3
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Thank you Tim

yes, I mean 125% faster.

Looks better on the 23.98 sequence. On the advanced settings of the AIC compressor, would it be best to leave it at "Others" or "HDV 720p"?

as for the DBeta, I think the post-house has a card, but just in case they don't and I have to do it in my own studio, what are my options without the Decklink/Kona card?
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Old November 14th, 2007, 11:07 AM   #4
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Originally Posted by Nima Taheri View Post
Looks better on the 23.98 sequence. On the advanced settings of the AIC compressor, would it be best to leave it at "Others" or "HDV 720p"?
HDV 720P seems to render almost indistinguishable results.
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as for the DBeta, I think the post-house has a card, but just in case they don't and I have to do it in my own studio, what are my options without the Decklink/Kona card?
Use compressor on a 24P export of the sequence and downconvert/compress into whatever NTSC tape format you need for your home studio...DV NTSC for example. Compressor 3 seems to be the smartest of all when adding the correct pulldown.
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Old March 2nd, 2008, 09:13 PM   #5
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Originally Posted by Tim Dashwood View Post

Use compressor on a 24P export of the sequence and downconvert/compress into whatever NTSC tape format you need for your home studio...DV NTSC for example. Compressor 3 seems to be the smartest of all when adding the correct pulldown.
Tim: I'm kinda new to Compressor, and I'm not sure exactly what you mean by the explanation.

Do you mean that I export the sequence, which is 23.98 as 24P, then use compressor to compress into whatever I need, which is 29.97 fps, and then put it on a sequence which is 29.97 in FCP and print to tape?

Also, what different options do I have when wanting to print a sequence to tape with the BRHD50 deck. Is this only possible through FCP?
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Old April 15th, 2008, 04:38 AM   #6
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anyone? bump
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Old April 15th, 2008, 10:17 AM   #7
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I just used this exact workflow on a recent music video:

We shot at 720/30p with the music playing at 125% (actually 124.2497%) speed with the intention of conforming to 23.98 to achieve a subtle larger-than-life look.

Here is what we did in post:

1. Ingest native hdv 29.97 (30p) footage

2. Transcode the hdv clips to an I-frame codec. (I used the batch list in MPEGstreamclip to convert all of my 720/30p hdv clips to Apple Pro-Res 10-bit HQ (220mbits))

3. Open CinemaTools and batch conform all of your fresh transcoded clips from 29.97 (30p) to 23.98 (NOT 24p). The conforming happens instantly, All of your conformed clips can now be opened and played back at 23.98.

4. Open up FCP with the proper codec and resolution selected. Make sure to select 23.98 as the editing timebase. Import clips and cut-away! Down convert to 10-bit digi-beta when the time comes.
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Old April 16th, 2008, 06:45 AM   #8
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Hunter

Thank you for the reply. I have done all the steps already, what I am unsure of is details of the last part. What I need is to record the sequence on a dv-tape using the BRHD50. Tim suggested that I use Compressor to export. This is where I'm stuck. This is the first project I am trying to record back to tape with FCP and the BRHD50. So, I'm not really sure how to work that workflow and get the correct pulldown, with the correct settings. Any help with the workflow from step 4 would be wildly appreciated.
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Old April 16th, 2008, 04:44 PM   #9
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So you want to take your finished 24p project and write it to 30p on tape? Or are you just having problems writing your project to tape? I'm a little confused.
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Old April 17th, 2008, 08:55 AM   #10
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i want to take the finished 24P project and write it to tape... and i'm trying to find the workflow on doing so.
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Old April 17th, 2008, 09:26 AM   #11
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Quote:
Originally Posted by Nima Taheri View Post
i want to take the finished 24P project and write it to tape... and i'm trying to find the workflow on doing so.
I apologize I didn't notice this thread in March.

So just to recap... you shot 720p30, then conformed it down to 720p24 (for slow motion) but then edited in a 720p30 sequence (or was it a 480i60 sequence?)

Quote:
Originally Posted by Nima Taheri
Do you mean that I export the sequence, which is 23.98 as 24P, then use compressor to compress into whatever I need, which is 29.97 fps, and then put it on a sequence which is 29.97 in FCP and print to tape?
I had given you the Compressor option as an alternative to outputting directly to DBeta via a Kona or Decklink. I should have explained it in more detail... and I will as soon as I get back to Toronto on my edit suite and I can take some screen grabs of compressor. I'm on my way home from NAB.

Quote:
Originally Posted by Nima Taheri
Also, what different options do I have when wanting to print a sequence to tape with the BRHD50 deck. Is this only possible through FCP?
It isn't only possible to export to tape via FCP. You can use DVHSCap or HDVxDV (I think) to output a 720p m2t back to the BR-HD50.
However there isn't much point in doing that since FCP supports print to tape.
In DV mode you can use "Edit to tape" for frame accurate assembly recording.
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Old April 18th, 2008, 04:45 AM   #12
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Originally Posted by Tim Dashwood View Post
I apologize I didn't notice this thread in March.

So just to recap... you shot 720p30, then conformed it down to 720p24 (for slow motion) but then edited in a 720p30 sequence (or was it a 480i60 sequence?)
No worries Tim.

I shot in 720p30, conformed to 23.98, but edited on a 720p/23.98 sequence (I can redo this on a 29.97 sequence if editing on the 23.98 sequence was wrong)?

Quote:
Originally Posted by Tim Dashwood View Post
I had given you the Compressor option as an alternative to outputting directly to DBeta via a Kona or Decklink. I should have explained it in more detail... and I will as soon as I get back to Toronto on my edit suite and I can take some screen grabs of compressor. I'm on my way home from NAB.
The only thing is that I don't have the Kona/Decklink. I'm recording straight to the BRHD50.
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Old April 18th, 2008, 12:16 PM   #13
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Is FCP's write to tape not working through firewire? Make sure your project settings match the deck and you should be fine.
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Old April 18th, 2008, 12:32 PM   #14
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Originally Posted by Nima Taheri View Post
No worries Tim.

I shot in 720p30, conformed to 23.98, but edited on a 720p/23.98 sequence (I can redo this on a 29.97 sequence if editing on the 23.98 sequence was wrong)?

The only thing is that I don't have the Kona/Decklink. I'm recording straight to the BRHD50.
You should always edit in the same frame rate as your source material when possible, so you've done everything correctly. If you were able to conform the footage in Cinema Tools then it must not be in HDV format anymore. Cinema Tools can't conform HDV footage unless it is re-encoded into an all I-frame codec like AIC or Pro-Res422.

The likely reason why you can't "print to tape" directly from your sequence is due to a codec mismatch. The BR-HD50 deck is expecting an mpeg2 stream. I would suggest that you make a new sequence using the HDV 720p30 preset and then just drag your other sequence into it. This is called nesting and will require rendering. Make sure to clear and in and out points in the original sequence before making the nest.
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