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24fps film - Telecine - to PAL Digibeta.


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#1 Fabian Prell

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Posted 27 April 2009 - 02:45 PM

Hi, I shot a project on Super 8 with 24fps

I live in the UK and want my project professionally telecined on to Digibeta

I have the following questions:

How is it done to ensure that the filmed speed will be right when looking at the film on tape, in other words:

PAL Standart is 25fps, I beleive that this is the speed that PAL Digibeta works at too. So there a following options:

1.The telecine runs at 25fps, so my film will run slightly faster then recorded. I can then transfer it into fcp and slow it down by 4%, and will have the image as it was, a 24fps speed.

2.Before tranfering on to PAL digibeta a 3:2pulldown takes place. In this case, wouldnt the flm run weird, (dropped frames or duplicated frames?)

How does it usually work and what is the best option to be able to edit it in the speed i actually recordet it.
I will record sound as well, that has to be synced with the image, so it is extremely important that i can edit at the same speed i recorded..

Thanks for the answers!
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#2 Oliver Christoph Kochs

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Posted 27 April 2009 - 03:17 PM

Telecine is always 1 frame = 2 fields. This will let your film run at the speed of 25 fps.
The pulldown you describe is always done by some filmtool-software that merges frames to fields to have a more fluid motion (instead of skipping a frame). There is newer software that uses much better methods for frame rate conversions without using fields and maintaining the progressive scan. The tube-type monitors TV are vanishing and the LCDs are better in displaying a progressive video.
There's LOTS of information here so keep reading...
Greetz Oliver
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#3 Fabian Prell

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Posted 27 April 2009 - 03:31 PM

Telecine is always 1 frame = 2 fields. This will let your film run at the speed of 25 fps.
The pulldown you describe is always done by some filmtool-software that merges frames to fields to have a more fluid motion (instead of skipping a frame). There is newer software that uses much better methods for frame rate conversions without using fields and maintaining the progressive scan. The tube-type monitors TV are vanishing and the LCDs are better in displaying a progressive video.
There's LOTS of information here so keep reading...
Greetz Oliver


Thanks for the reply!
What I am asking though, is:

If I shoot at 24fps, but the transfer to Digibeta happens at 25fps. And I then import this footage into final cut pro to edit it, wont it be 1frame per second too fast? Wont I have to slow it down again to get the speed, that the action happened at, when recorded in 24 fps?

The method to achieve this would be some kind of pulldown or simply a reduction of the clip speed in final cut pro. But would I have to do that in the first place or do the guys at lab ensure somehow that it will be on the Digibeta tape in exactly the speed I recorded it.

Thanks!
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#4 Robert Houllahan

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Posted 27 April 2009 - 05:25 PM

Telecine is always 1 frame = 2 fields. This will let your film run at the speed of 25 fps.
The pulldown you describe is always done by some filmtool-software that merges frames to fields to have a more fluid motion (instead of skipping a frame).



Sorry that is (almost) completely wrong ;) Telecine in NTSC countries is 1frame = 2 fields then 1 frame = 3 fields i.e. the 2:3 pulldown which happens in the telecine's framestore (not software, hardware) for 29.97 fps NTSC.

PAL countries and PAL Telecine is 1 frame = 2 fields at 25fps no 2:3 pulldown because that is for NTSC. You can use FCP's Cinema tools to conform the 25fps material to 23.98 fps once it is captured.

-Rob-
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#5 Dirk DeJonghe

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Posted 27 April 2009 - 11:31 PM

In PAL SD, what you do is run the picture at 25fps, adjust the pitch of the audio if required (rarely done). I would say that the very large majority of feature films shown on PAL TV effectively run at 25 fps projection speed. If you run a PAL telecine at 24fps it will freeze one frame per second giving jerky pans.
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#6 Daniel Porto

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Posted 28 April 2009 - 04:09 AM

PAL countries and PAL Telecine is 1 frame = 2 fields at 25fps no 2:3 pulldown because that is for NTSC. You can use FCP's Cinema tools to conform the 25fps material to 23.98 fps once it is captured.

-Rob-


Can't you also do 24p or 25p for telecine?
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#7 Brian Drysdale

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Posted 28 April 2009 - 11:14 AM

Can't you also do 24p or 25p for telecine?


It can be done, but in the PAL countries 25 fps is normal, especially when going to a standard video format like Digibeta. You won't notice any difference motion wise, although the film's overall running time will be shorter. But, somehow, this running timing change seems to be more noticeable when playing back 25fps at 24fps rather than the other way around.

Any audio pitch changes need to be handled with care, some music doesn't like going through the process.
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#8 Kent Kumpula

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Posted 28 April 2009 - 12:09 PM

Can't you also do 24p or 25p for telecine?


No. The file you will receive will play at 25fps. Just telecine it with 25fps, this way you will get 100% fluid motion and 100% progressive images.

If you want to play with pulldown to change the speed to 24fps (adding one extra frame per second) you can do this while editing. But you will get better results if you speed up the audio and play the videofile at 25fps.

By getting the telecine done with 25fps you have all the options left. If you choose to transfer at 24fps it will be much more difficult to get rid of the pulldown if you´d want to try with a 25fps version.
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#9 Robert Houllahan

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Posted 28 April 2009 - 12:23 PM

Can't you also do 24p or 25p for telecine?



You can run the telecine at 24fps to transfer to 25fps but if you are transferring to a SD format it will be interlaced no matter what you do. The film is always progressive and a telecine will scan a progressive picture then place that frame onto the video format's fields. You can easily re time the video in software after transfer. i.e. the 25fps PAL video and be re timed to 24fps in cinema tools if you want to work in 24fps time base for DVD delivery.

-Rob-
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#10 Fabian Prell

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Posted 28 April 2009 - 02:50 PM

Thanks for all the answer guys.

I think its really weird that a film filmed on 24fps just runs 4% faster on PAL DVDs and TV and noone cares, if this is true. So the common thing to do is to just let it run faster? Is there no technical way of getting a film on a DVD in a PAL country and actually see it at the original speed it was recorded? It sounds weird to me (I know that Blu-Ray films are now universally 24p and that HDTVs are including this native 24p support more and more to replicate a cinema projection), but still, with SD there is no option get a 24fps film in the right speed on a PAL TV with progressive pictures?

Even if I wouldn't see it, just knowing it would annoy the crap out of me.. am I missing something?
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#11 Brian Drysdale

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Posted 28 April 2009 - 05:53 PM

The DVD frame rates are listed here: http://en.wikipedia.org/wiki/DVD-Video

A PAL television will display the Region 1 DVDs, although what the UK DVD player does with a 23.98fps DVD is another matter, I've only seen 29.97fps using my player.

I suspect 24fps could produce post production problems if your facility isn't set up for it. Also PAL Digital Betacam is only 25fps, it'll split your frame into two fields, but the effect is same as progressive. So, you'd need to find another method of recording if you want 24fps.

Edited by Brian Drysdale, 28 April 2009 - 05:55 PM.

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#12 John Sprung

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Posted 29 April 2009 - 01:11 AM

So the common thing to do is to just let it run faster? Is there no technical way of getting a film on a DVD in a PAL country and actually see it at the original speed it was recorded?


Yup, running everything a tad faster in PAL is what everybody does. It works fine, almost nobody can detect the difference. The interpolation to make an extra frame out of every 24 frames is extremely difficult, and has never been done in a way that looks adequate.





-- J.S.
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#13 Fabian Prell

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Posted 29 April 2009 - 07:55 PM

Yup, running everything a tad faster in PAL is what everybody does. It works fine, almost nobody can detect the difference. The interpolation to make an extra frame out of every 24 frames is extremely difficult, and has never been done in a way that looks adequate.





-- J.S.



I want my money back - is probably the best way to describe what I feel right now. All these years growing up, watching Pinocchio's nose grow 4% faster, because I was in the UK..... I can't believe that there is no standardization that all movies in the world run at the same speed, no matter if DVD, Bluray, cinema projection, PAL, NTSC... All the years of watching movies too quick.. Schwarzenegger's voice on baloongas (or 4% less manly). Its 2009!

I guess next time my girlfriend forces me to watch "Love actually" for the 5380th time I will just get the PAL version ;).

Anyways, slightly off topic, apologies... felt like my parents just told me theres no santa clause...
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#14 Brian Drysdale

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Posted 30 April 2009 - 11:31 AM

Anyways, slightly off topic, apologies... felt like my parents just told me theres no santa clause...


Just to add to your sense of loss, some cinemas do the same thing.
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#15 Agustin Goya

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Posted 09 May 2009 - 01:00 AM

Anyways, slightly off topic, apologies... felt like my parents just told me theres no santa clause...

Don't worry! this mean that you've been watching 4.1% faster movies all your life and you didn't noticed. the only thing that changed is that now, you know how it's done, but the movies will remain the same.
You've been watching fully progressive frames all you life , while in NTSC movies have the same duration as 24fps film, but have interlaced frames in it!!!! :D
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#16 Neil B Sadwelkar

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Posted 01 June 2009 - 10:36 PM

I think everyone seems to have missed the point.

The poster asked, for a film shot at 24fps, if the telecine was at 25fps, wouldn't it be fast? Answer is yes it would be 4% fast. If you capture that to FCP you need to 'conform' it to 24fps so it goes back to playing at the right speed and syncs with sound if any was recorded on a separate machine. The timeline you edit on is also 24fps.

On an Avid, you capture 25fps from tape into a film project and Avid automatically converts that to 24fps and preserves the number of frames. Hence slows it down by 4%

Here, in PAL film editing 24fps is TRUE 24fps not 23.98 as is used in NTSC countries.

This is how we've been editing movies for over a decade now on NLEs. And hundreds of movies get edited exactly using this principle, in PAL countries.

More on this '24-25 thing' in PAL film editing on my blog. Not sure I can add a link to that here, so
Just Google 'The 24-25 issue in PAL film editing'

Edited by Neil B Sadwelkar, 01 June 2009 - 10:37 PM.

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#17 Brian Drysdale

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Posted 02 June 2009 - 07:33 AM

The poster asked, for a film shot at 24fps, if the telecine was at 25fps, wouldn't it be fast? Answer is yes it would be 4% fast. If you capture that to FCP you need to 'conform' it to 24fps so it goes back to playing at the right speed and syncs with sound if any was recorded on a separate machine. The timeline you edit on is also 24fps.

On an Avid, you capture 25fps from tape into a film project and Avid automatically converts that to 24fps and preserves the number of frames. Hence slows it down by 4%

Here, in PAL film editing 24fps is TRUE 24fps not 23.98 as is used in NTSC countries.


You can edit in 24 fps with the sound synced up, it's another matter when the master of the competed film gets played back on a Digibeta player which plays at 25fps.
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#18 Eugene Lehnert

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Posted 09 June 2009 - 05:05 PM

If you want the PAL video to run at the same speed as the 24p master you can run the video through an Alchemist or UKON. These boxes can do video conversions interpolating new frames so that the speed is the same. The Alchemist has a higher quality motion compensated algorithm than the UKON. This does lower the quality of the image though.

If you bring the sped up PAL video into Final Cut you will want to reconform the video so that the files play back at the different speed. Dropping the files into a Final Cut Pro timeline will not work. Final Cut will merely toss out or insert frames. You want the frames to remain intact and not be interpolated in any way. This can be done using Shake or After Effects. But PAL has a different resolution than NTSC so this is another issue.
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#19 Neil B Sadwelkar

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Posted 10 June 2009 - 08:16 AM

If you want the PAL video to run at the same speed as the 24p master you can run the video through an Alchemist or UKON. These boxes can do video conversions interpolating new frames so that the speed is the same. The Alchemist has a higher quality motion compensated algorithm than the UKON. This does lower the quality of the image though.


You can do the same with a 24fps Quicktime in Apple Compressor. With careful application of settings you can get a 25fps Quicktime which has the same duration. The extra frame needed every second is cleanly generated.

Neil Sadwelkar
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