24fps shooting vs. 23.976
Posted 28 April 2012 - 04:24 PM
Posted 02 May 2012 - 09:48 AM
You will edit at 23.976 in your NLE. HD cameras will nearly always be shooting video at 23.976. This frame-rate will convert to 29.97 SD or 59.94i HD using a 2-3 pulldown. If you had a true 24 signal it would convert into a 30 fps SD signal or a 60i HD signal. For video work you want 23.976. Then if you need to go film the HD master you create can be sped back up to 24p for a film-out or DCP.
People use 23.976 and 24p interchangeably though. So you might need clarification at times as to what someone really needs or is using.
The other catch is that your timeline will also not reflect time properly. If you think your film is 1-hour at 23.976 it's actually longer because you are playing your film slower than the 24 frame timecode. This is why drop-frame exists in SD. Timecode numbers are skipped at regular intervals so that the timecode stays accurate to length.
What is the difference? When a NLE system reads 24 fps does it mean 23.976? Or vise versa? Do I need a crystal synch motor to do both 24fps and 23.976? Is one or the other best for the 2:3 pull down or something like that? Help, please I'm about to pick the speeds to order on my crystal synch motor.
Posted 02 May 2012 - 10:36 AM
The telecine house said 24 so now I'm a little confused.
Posted 02 May 2012 - 10:53 AM
If you shoot at 23.976 it will be slowed down again when you transfer it to video.
Shoot true 24. Edit 23.976. Slow your on set audio down too.
Edited by Eugene Lehnert, 02 May 2012 - 10:58 AM.
Posted 02 May 2012 - 11:05 AM
Posted 02 May 2012 - 01:03 PM
Japan has NTSC but they run their tv at 30fps and their analog black levels are at 0 IRE instead of 7.5 IRE that we have here in the states. We suffer because we had it all first. Maybe the internet will undo all of this one day.
Posted 02 May 2012 - 01:46 PM
Posted 02 May 2012 - 05:50 PM
Posted 03 May 2012 - 03:44 AM
Should I get 8, 12, 48 or 60? I would use slo mo but probably not undercrank. Besides I could do fast speed on nle but slo mo suffers in nle so that answers that. What would be a better slo mo speed, 48 or 60? Probably 60 because I could always speed it up but it would take a bigger battery.
I'd get 48 fps before having 8fps. I think I've used 18 fps more than anything below 12 fps.
Posted 03 May 2012 - 01:28 PM
1. Are the movies on HBO running at a different speed than they were shot in?
2. What format do cable networks buy/broadcast, HD Tape, Digibeta, what?
3. Can someone confirm this procedure: shoot 24 then transfer to hard drive at 29.97, edit then export to tape for broadcast at 29.97 1080p???
Is that it?
Posted 03 May 2012 - 04:47 PM
If you shoot 24 it will be slowed down to 23.976 for video. If you are making film prints from your negative there will be no speed change because projectors run at 24fps. If you shoot 23.976 on film, transfer it to video and finish in firstname.lastname@example.org and then transfer the video to film it will be sped back up to 24. HDCAMSR decks do this all the time. I can take a 23.976 tape and play it at 24fps or 25fps if I want. The speed change is minor and happens all the time.
The big issue is syncing external audio to your film transfers. They both need to run at the same speed to stay in sync. When you shoot 24fps on your camera the telecine slows the film to 23.976 so you have to slow your audio down by the same percentage. If you shoot 23.976 the telecine will play back the film at the speed you shot so there is no slow-down. In this instance the audio does not need to be adjusted to stay in sync with the picture. If you shoot 23.976 and try and sync audio up the audio on a film bench the audio will drift because the film is playing back at 24fps in the projector and it's now running faster then when it was recorded.
The usual workflow is: Shoot 24, transfer to 23.976 or 29.97, slow-down the audio, sync the audio, edit and output a 23.976 or 59.94 HD master. I would suggest creating a 23.976 master first and then adding the pull-down to create the email@example.com Drop-Frame broadcast tape. You just have to keep in mind that the timecode on a 23.976 timeline is not an accurate measure of time. Your film is actually running longer than what it is telling you.
I hope I haven't given you too much information to make it confusing.
Edited by Eugene Lehnert, 03 May 2012 - 04:49 PM.
Posted 08 May 2012 - 07:52 AM
Posted 08 May 2012 - 11:03 AM
You get used to it really quick.
It's threads like this that make me really glad to live (and shoot) in PAL land.