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ROCKMORE
11-27-2009, 12:42 PM
How does 23.976 differ from straight 24fps as a frame rate?

How does it effect post production decisions in PAL vs NTSC?

I've been shooting film for years at 24fps and in telecine (what ever the frame rate shot in film) would either be transferred to 29.97 NTSC or 25fps PAL.

What is the technical purpose of 23.976?

Cranky
11-27-2009, 02:51 PM
How does 23.976 differ from straight 24fps as a frame rate?
It is slower.


What is the technical purpose of 23.976?
To acquire, edit and master in native progressive format with frame rate friendly to 60Hz video systems. Proper cinema video cameras like the HDW-F900 Cinealta shoot 24.00 fps, but still have to be slowed down to 23.976 for TV/DVD distribution.

Some related info:
http://www.hometheaterhifi.com/the-dvd-benchmark/177-dvd-benchmark-part-5-progressive-scan-dvd.html
http://en.wikipedia.org/wiki/Telecine
http://en.wikipedia.org/wiki/Progressive_segmented_Frame

Martti Ekstrand
11-27-2009, 04:24 PM
23.976 is a frame rate derived from the 59.94 field rate of NTSC. If NTSC really was 60 fields / 30 frames per second then 24 fps would make a even 2.3 pulldown cadence. So all these years when you had shot on film at 24 fps it was actually played in the telecine at 23.976 or every 1000 frame was skipped entirely for NTSC transfer but I bet the telecine operator never bothered you with those little technical tidbits. Messy format innit?

Barry_Green
11-27-2009, 04:28 PM
Messy format innit?
It's a complete mess. Fortunately, when we went to HD, they fixed it and re-standardized on 24fps/60.

Oh wait... no they didn't... Grrr...

ROCKMORE
11-27-2009, 06:26 PM
It's a complete mess. Fortunately, when we went to HD, they fixed it and re-standardized on 24fps/60.

Oh wait... no they didn't... Grrr...

It does sound a little messy.
So for my project planned to be finished in both NTSC & PAL what will be the best to shoot everything at for the smoothest quality master file out of the choices I have, 24p (23.976) / 25p, 1280 x 720 (HD): 60p (59.94) / 50p,

I plan to shoot a mix between real time and slow motion so a in the interest of some post continuity it may be better to remain at 1280 x 720.

Martti Ekstrand
11-27-2009, 11:10 PM
I'd say 25p - you have a good clean looking PAL master compatible with 80% of the world's broadcast systems. Then as been said a number of times, slow that final master down frame-by-frame to 23.976 and add a pulldown for 29.97 NTSC broadcast. Now you have a NTSC dub that looks just like all movies telecined for NTSC. IE: the around here much coveted 'film look' cadence.

Or you could do everything in 24p, speed up frame-by-frame for PAL dub and still do a pulldown 29.97 NTSC dub- it depends on where you think the timing change is worse. A slow-downed NTSC or a speeded PAL. Either way you get the around here much coveted 'film look' cadence. But this method means both dubs will need work.

The one master frame rate to avoid is 29.97, then a lot of people around here (and elsewhere) will claim 'it looks like soap opera video', the PAL version will be a mush of blended frames and should you ever want to strike a film print from that master... well, then you are far up in Crap Creek with not even a toilet seat to paddle with.

Shoot as much as possible in 1080 and only do the slow-motion parts in 720, 60p or 50p even if you go for 720 as a final master resolution.

ROCKMORE
11-28-2009, 01:42 AM
I'd say 25p - you have a good clean looking PAL master compatible with 80% of the world's broadcast systems. Then as been said a number of times, slow that final master down frame-by-frame to 23.976 and add a pulldown for 29.97 NTSC broadcast. Now you have a NTSC dub that looks just like all movies telecined for NTSC. IE: the around here much coveted 'film look' cadence.

Or you could do everything in 24p, speed up frame-by-frame for PAL dub and still do a pulldown 29.97 NTSC dub- it depends on where you think the timing change is worse. A slow-downed NTSC or a speeded PAL. Either way you get the around here much coveted 'film look' cadence. But this method means both dubs will need work.

The one master frame rate to avoid is 29.97, then a lot of people around here (and elsewhere) will claim 'it looks like soap opera video', the PAL version will be a mush of blended frames and should you ever want to strike a film print from that master... well, then you are far up in Crap Creek with not even a toilet seat to paddle with.

Shoot as much as possible in 1080 and only do the slow-motion parts in 720, 60p or 50p even if you go for 720 as a final master resolution.

Thanks Martti, That sums it up quite nicely.

Cranky
11-28-2009, 08:29 AM
I'd say 25p - you have a good clean looking PAL master compatible with 80% of the world's broadcast systems. Then as been said a number of times, slow that final master down frame-by-frame to 23.976 and add a pulldown for 29.97 NTSC broadcast. Now you have a NTSC dub that looks just like all movies telecined for NTSC. IE: the around here much coveted 'film look' cadence.
"much coveted 'film look' cadence" has nothing to do with 2-3 pulldown. Both 24p and 2-3 pulldown are technical necessities, but the latter adds rhythmic jerky motion which is non-characteristic for a pure movie look, and is despised in PAL land.


The one master frame rate to avoid is 29.97, then a lot of people around here (and elsewhere) will claim 'it looks like soap opera video', the PAL version will be a mush of blended frames and should you ever want to strike a film print from that master... well, then you are far up in Crap Creek with not even a toilet seat to paddle with.
Did you mean progressive or interlaced? Progressive 30p is to avoid because it does not convert well to 50Hz system. 30i is to avoid by fanatics of "movie look" because it has "live" look. You should be more precise in your statements.

As to what rate to shoot, I'd say shoot everything in 50p if you don't know where slo-mo will be. Then you can either keep 'live' look or drop frames to achieve 25p, or slow down to achieve nice 0.5 slo-mo.

ROCKMORE
11-28-2009, 03:39 PM
"much coveted 'film look' cadence" has nothing to do with 2-3 pulldown. Both 24p and 2-3 pulldown are technical necessities, but the latter adds rhythmic jerky motion which is non-characteristic for a pure movie look, and is despised in PAL land.


Did you mean progressive or interlaced? Progressive 30p is to avoid because it does not convert well to 50Hz system. 30i is to avoid by fanatics of "movie look" because it has "live" look. You should be more precise in your statements.

As to what rate to shoot, I'd say shoot everything in 50p if you don't know where slo-mo will be. Then you can either keep 'live' look or drop frames to achieve 25p, or slow down to achieve nice 0.5 slo-mo.

What would you suggest as the best place to start for mastering footage with my ultimate need to have both NTSC and PAL versions for distribution, 24p or 25p? And how would you process the footage in post?