Editing film at 30fps

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Editing film at 30fps

I'm shooting a feature on Super16 in a couple months, and I've recently talked to a film lab that can handle the processing and telecine (ColorLab in Rockville, MD if you must know).

For some background, we want to get the film in the can and put it on video to edit, as well as put it on DVD for promo purposes. Then, if all goes well, we would go back to the source and have it blown up to 35mm. So yes, we want to use our telecine footage, but the primary focus is on ultimately conforming the original negative.

The person there said that there's basically no way FCP can reverse telecine the footage to edit at 24fps, because the mathematical formula wouldn't match and the negative wouldn't be cut correctly. He said I'd have to edit it at the standard NTSC rate instead.

Is this acceptable? And if so, what are the things I need to know? I understand that it means you can basically only edit in 4-frame increments to ensure that edits are on the A-frame. Is there any way around that, and/or how much of a pain is it?

The other concern I have is audio. The guy at the lab said to record the audio with 30fps NDF timecode, but what about the difference in speed, as the film will be slowed down a bit in order to conform to 29.97fps? Should I record the sound in true 30fps and then slow it down so that both the video and audio are slightly slower than originally recorded, and then bring it back up to true speed if/when the negative is conformed and the answer print made? How do I go about adjusting the speed like that?

Should I consider finding a different telecine lab to do a true 3:2 pulldown or 1:1 transfer?

Any help is greatly appreciated, as there is obviously no small amount of confusion on my part over how to handle this.

iMac G5 Mac OS X (10.4.7)

Posted on Aug 14, 2006 3:35 PM

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Answer 1

ckahn

Level 1

18 points

Aug 14, 2006 10:19 PM in response to smack5099

The other concern I have is audio. The guy at the
lab said to record the audio with 30fps NDF timecode,
but what about the difference in speed, as the film
will be slowed down a bit in order to conform to
29.97fps? Should I record the sound in true 30fps
and then slow it down so that both the video and
audio are slightly slower than originally recorded,
and then bring it back up to true speed if/when the
negative is conformed and the answer print made? How
do I go about adjusting the speed like that?

If the sound is transferred during telecine, the telecine place will handle the speed change.

Should I consider finding a different telecine lab to
do a true 3:2 pulldown or 1:1 transfer?

You didn't mention the 1:1 transfer bit above. (A 1:1 transfer would explain why reverse telecine wouldn't work.) A transfer with 3:2 pulldown would be preferred.

If you transfer at 1:1, that would mean 24fps picture would be sped up when played at ntsc video's 29.97 fps. Audio would also be sped up. You could try using Cinema Tools's Conform feature to re-speed the 29.97 FCP media to 23.98 fps. But how are the keykode numbers getting into FCP/CT for your final neg conform? Is it burn-in only or will there be film transfer logs from the telecine facility?

Dual 2 GHz PowerPC G5 Mac OS X (10.4.3)

Dual 2 GHz PowerPC G5 Mac OS X (10.4.3)

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Answer 2

smack5099 Author

Level 1

0 points

Aug 15, 2006 2:10 PM in response to ckahn

If the sound is transferred during telecine, the
telecine place will handle the speed change.

The sound won't be transferred during telecine. I'll be doing that in FCP because of cost. Even if the sound was being transferred, though, I want to be able to use the digital files to conform to the answer print, since we're recording to hard disk. So it would still have to be sped up to match the film.

Should I consider finding a different telecine lab

to

do a true 3:2 pulldown or 1:1 transfer?

You didn't mention the 1:1 transfer bit above. (A
1:1 transfer would explain why reverse telecine
wouldn't work.) A transfer with 3:2 pulldown would
be preferred.

No, they don't offer a 1:1 transfer. I was mentioning the things above as an alternative to what this lab offers.

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Answer 3

ckahn

Level 1

18 points

Aug 15, 2006 10:45 PM in response to smack5099

If the sound is transferred during telecine, the
telecine place will handle the speed change.

The sound won't be transferred during telecine. I'll
be doing that in FCP because of cost. Even if the
sound was being transferred, though, I want to be
able to use the digital files to conform to the
answer print, since we're recording to hard disk. So
it would still have to be sped up to match the film.

The Cinema Tools conform option can alter the speed to 23.98, 24, 29.97 or 30, but only for video or video+audio clips, not audio-only clips.

Should I consider finding a different telecine

lab

to

do a true 3:2 pulldown or 1:1 transfer?

You didn't mention the 1:1 transfer bit above. (A
1:1 transfer would explain why reverse telecine
wouldn't work.) A transfer with 3:2 pulldown

would

be preferred.

No, they don't offer a 1:1 transfer. I was
mentioning the things above as an alternative to
what this lab offers.

If the lab offers 2:3 pulldown, then they shouldn't be saying that Cinema Tools reverse telecine wouldn't work, because it would.

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Answer 4

smack5099 Author

Level 1

0 points

Aug 21, 2006 2:43 AM in response to ckahn

The sound won't be transferred during telecine.

I'll
be doing that in FCP because of cost. Even if the
sound was being transferred, though, I want to be
able to use the digital files to conform to the
answer print, since we're recording to hard disk.
So
it would still have to be sped up to match the film.

The Cinema Tools conform option can alter the speed
to 23.98, 24, 29.97 or 30, but only for video or
video+audio clips, not audio-only clips.

In that case, should I record the sound in pulldown mode (i.e. slightly higher than 48khz) so it will be slowed down in the editing system. Could I then use the OMF files for conforming and have them brought up to their original sampling rate?

Or should I record in true 30fps and then conform the telecined footage to true 30fps along with it. Then the OMF files would match the negative.

And for making a DVD, I could bring it all down to 29.97 in compression (or could I?).

If the lab offers 2:3 pulldown, then they shouldn't
be saying that Cinema Tools reverse telecine wouldn't
work, because it would.

Well, maybe it would, but I don't think that's a risk worth taking. If they're right (and they probably know what they're doing having been in business as long as they have),I could edit the film and give it to the negative matcher only to have everything come out wrong, an outcome I'd consider just slightly worse than waking up with thirty king cobras in my bed. What I want to know is how much of a pain it is to do the edit at 30fps and conform back to the negative.

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Answer 5

ckahn

Level 1

18 points

Aug 21, 2006 5:48 AM in response to smack5099

The sound won't be transferred during telecine.

I'll be doing that in FCP because of cost. Even if
the sound was being transferred, though, I want to be
able to use the digital files to conform to the
answer print, since we're recording to hard disk.
So it would still have to be sped up to match the

film.

The Cinema Tools conform option can alter the

speed

to 23.98, 24, 29.97 or 30, but only for video or
video+audio clips, not audio-only clips.

In that case, should I record the sound in pulldown
mode (i.e. slightly higher than 48khz) so it will be
slowed down in the editing system. Could I then use
the OMF files for conforming and have them brought up
to their original sampling rate?

Or should I record in true 30fps and then conform the
telecined footage to true 30fps along with it. Then
the OMF files would match the negative.

Sound speed depends on camera speed. If camera is running at 24 fps, sound should be 30 fps, if camera can run at pulldown 23.98 fps, sound should be pulldown 29.97 fps. Matching pulldown with non-pulldown will cause audio to drift.

And for making a DVD, I could bring it all down to
29.97 in compression (or could I?).

I believe if you gave DVD Studio Pro a 30fps quicktime, it would give you a 29.97fps DVD, but you should check the manual.

If the lab offers 2:3 pulldown, then they shouldn't
be saying that Cinema Tools reverse telecine wouldn't
work, because it would.

Well, maybe it would, but I don't think that's a risk
worth taking. If they're right (and they probably
know what they're doing having been in business as
long as they have),

The lab's expertise lies in the film transfer business, not in the Cinema Tool reverse telecine business. I wouldn't go to a lab for advice on how to use Cinema Tools.

I could edit the film and give it
to the negative matcher only to have everything come
out wrong, an outcome I'd consider just slightly
worse than waking up with thirty king cobras in my
bed. What I want to know is how much of a pain it is
to do the edit at 30fps and conform back to the
negative.

It's a pain because at 30fps you don't have a 1:1 relationship between the video frames and your original film frames. Reverse telecine creates that 1:1 relationship.

Is the lab giving you keykode burn on the footage? With keykode burn it is easy to verify that the numbers you are giving to the negative cutter match what you are expecting.

Why don't you get a test tape from the lab and reverse telecine it for yourself to see how it works? It's a very straighforward procedure in Cinema Tools that takes 30 fps 3:2 video, recombines the fields and turns it into 24 (or 23.98) fps video.

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Answer 6

smack5099 Author

Level 1

0 points

Aug 21, 2006 10:25 AM in response to ckahn

Well, maybe it would, but I don't think that's a

risk

worth taking. If they're right (and they probably
know what they're doing having been in business as
long as they have),

The lab's expertise lies in the film transfer
business, not in the Cinema Tool reverse telecine
business. I wouldn't go to a lab for advice on how
to use Cinema Tools.

I talked to them again today, and I think you may be right. The guy didn't know what Nattress was when I brought it up, didn't seem at all familiar with Cinema Tools, and said he hadn't used Final Cut in four years.

Why don't you get a test tape from the lab and
reverse telecine it for yourself to see how it works?

They don't have any footage for a test tape. I think I'll contact the rental house we're using and try shooting a sync test along with a standard camera test. It's probably worth the extra roll of stock and processing/telecine fees to be sure. And then I'll have a junk roll to use on set for demonstrations of the mag-loading process.

Thanks for the help.

BTW, how easy or difficult is it to take a 24p sequence and output it to the NTSC frame-rate if I want to make a DVD out of the footage (while we wait/pray for funds for the answer print/blowup)? I know Nattress can do it, but I'm wondering if it can be done easily and effectively native to FCP.

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Answer 7

ckahn

Level 1

18 points

Aug 21, 2006 10:54 AM in response to smack5099

Thanks for the help.

You're welcome.

BTW, how easy or difficult is it to take a 24p
sequence and output it to the NTSC frame-rate if I
want to make a DVD out of the footage (while we
wait/pray for funds for the answer print/blowup)? I
know Nattress can do it, but I'm wondering if it can
be done easily and effectively native to FCP.

DVD Studio Pro will take 23.98 quicktime file exported from FCP and make a 29.97 DVD from it, without any extra steps. If you want to compress the audio to AC3, you can use Compressor.

Dual 2 GHz PowerPC G5 Mac OS X (10.4.3)

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Answer 8

smack5099 Author

Level 1

0 points

Aug 21, 2006 2:10 PM in response to ckahn

Thanks for the help.

be done easily and effectively native to FCP.

DVD Studio Pro will take 23.98 quicktime file
exported from FCP and make a 29.97 DVD from it,
without any extra steps. If you want to compress the
audio to AC3, you can use Compressor.

Okay, so when I do the reverse telecine I should use 23.98 rather than true 24fps. And I would record the field audio at a slightly faster sampling rate (48.048khz) so it'll match the video when played at 48khz (assuming I'm really anal and don't even like the idea of a 1/10 sec. drift over a two-minute scene). From that, I would burn my DVD. And then eventually the audio postproduction facility would take the audio and speed it up to the original record speed for conforming to the answer print (so it doesn't drift five seconds over the course of the feature).

Do I have it now? 😉

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Answer 9

ckahn

Level 1

18 points

Aug 21, 2006 3:06 PM in response to smack5099

Thanks for the help.

be done easily and effectively native to FCP.

DVD Studio Pro will take 23.98 quicktime file
exported from FCP and make a 29.97 DVD from it,
without any extra steps. If you want to compress

the

audio to AC3, you can use Compressor.

Okay, so when I do the reverse telecine I should use
23.98 rather than true 24fps.

Use 23.98 instead of 24 if you want the video to play back on an NTSC monitor. If you are just playing on your computer monitor, then 23.98 won't matter.

And I would record the
field audio at a slightly faster sampling rate
(48.048khz) so it'll match the video when played at
48khz (assuming I'm really anal and don't even like
the idea of a 1/10 sec. drift over a two-minute
scene). From that, I would burn my DVD. And then
eventually the audio postproduction facility would
take the audio and speed it up to the original record
speed for conforming to the answer print (so it
doesn't drift five seconds over the course of the
feature).

Do I have it now? 😉

If you can record at 48.048 kHz while your camera is running at 24 fps, then pulling down to 48 kHz and 23.98 fps should work fine.

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