HD Question for Mattias or Cristof or anyone that knows....
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- freddiesykes
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"24PsF means 24P stored on tape as two fields (PsF = progressive segmented frames) that are recombined during playback into P frames. There is no pulldown added. PsF was a Sony invention when they made the first 24P cameras, so they only had to change the Hz rate of the cameras (and the CRT monitoring) from 60 to 48 for recording/playback."
-David Mullen ASC
-David Mullen ASC
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A 24p camera will capture images at 24 individual non-interlaced frames a second, and store them as such in its native format.
Best thing to do from there on out is always work with formats which are frame rate independant (DivX, XviD, x264, etc), as everything's distributed digitally now anyway.
You can then leave it up to the end users' decoding hardware to output correctly for the display. For example, my "DVD" player also plays h264 and XviD, and will automatically detect the video system type and output appropriately (PAL as I'm in Europe), and adjusts to match. Obviously on a decent modern display there'll be no issues outputting @ pure 24fps over HDMI or DVI.
Best thing to do from there on out is always work with formats which are frame rate independant (DivX, XviD, x264, etc), as everything's distributed digitally now anyway.
You can then leave it up to the end users' decoding hardware to output correctly for the display. For example, my "DVD" player also plays h264 and XviD, and will automatically detect the video system type and output appropriately (PAL as I'm in Europe), and adjusts to match. Obviously on a decent modern display there'll be no issues outputting @ pure 24fps over HDMI or DVI.
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http://en.wikipedia.org/wiki/Panasonic_AG-HVX200
and
http://en.wikipedia.org/wiki/Canon_XL-2
Offer native 24p support, however, the newer http://en.wikipedia.org/wiki/Canon_XL_H1 offers "24f" aka 48i support, but stored to tape as 24p.
and
http://en.wikipedia.org/wiki/Canon_XL-2
Offer native 24p support, however, the newer http://en.wikipedia.org/wiki/Canon_XL_H1 offers "24f" aka 48i support, but stored to tape as 24p.
25p should indeed be exactly 25p, not 24.975. That's a trick indigenous to NTSC only because for some reason the idiot engineers that designed the system thought it would be easier the slow down the frame rate by .1% instead of increasing the audio bandwidth by .1% so the PAL standards don't suffer that. Since there's no pulldown method to go from 25fps to 29.97, it's not necessary to use the same technique.
I may sound stupid, but I hide it well.
http://www.gcmstudio.com
http://www.gcmstudio.com
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24p, 23.976p and 25p are all distinct frame rates
24p in PAL world does mean exactly 24 fps and not 23.976p like in NTSC.
23.976p exist because NTSC is actually 29.97.
For 24 vs 23.976. It all depends on your workflow - often on your audio and post workflow. They are both easily transferable to film.
For 24p being played back using PAL telecine - there are 2 methods used. The 'dumbed down' version is 24+1. Basically, frame redundancy.
The more traditional is 12p + 12i + 1p (or 12+1 for short). Don't ask the exact details, but it is basically means after the 12th frame, the frame is broken down at the field level.
DVC Pro cameras can capture in 24p frames and store them in a 60p stream. But for all intent and purpose - it is 24p frames per second (or 23.976 if you want to be pedantic in the NTSC world). This is because Panasonic's DVC Pro codec was designed around the idea of 720/60p.
P2 DVC PRo HD cameras can store the 24p stream in a 24fps file. So there is no 24p over 60p trickery.
HDCAM can also do 24p and store it as 24PsF.
Some cameras (BUT NOT ALL) do capture at 24p and store interlace format. For many reasons. One of them is the limitation of the supported tape format. For example, DV 24p cameras is limited by the DV specifications. CAnon 24f is not actual 24p. It is the CCD doing 48i scan cycle - insted of 24p.
And yes there is 48i in HDV - it is 24f
2. Yes. 24p exact would be converted to 23.976p somewhere down the process - like when mastering to tape for delivery. Since all NTSC broadcast standards are all 23.976/29.97/59.94 variants. There is no way to get around .1 NTSC factor for TV transmission.
24p in PAL world does mean exactly 24 fps and not 23.976p like in NTSC.
23.976p exist because NTSC is actually 29.97.
For 24 vs 23.976. It all depends on your workflow - often on your audio and post workflow. They are both easily transferable to film.
For 24p being played back using PAL telecine - there are 2 methods used. The 'dumbed down' version is 24+1. Basically, frame redundancy.
The more traditional is 12p + 12i + 1p (or 12+1 for short). Don't ask the exact details, but it is basically means after the 12th frame, the frame is broken down at the field level.
DVC Pro cameras can capture in 24p frames and store them in a 60p stream. But for all intent and purpose - it is 24p frames per second (or 23.976 if you want to be pedantic in the NTSC world). This is because Panasonic's DVC Pro codec was designed around the idea of 720/60p.
P2 DVC PRo HD cameras can store the 24p stream in a 24fps file. So there is no 24p over 60p trickery.
HDCAM can also do 24p and store it as 24PsF.
Some cameras (BUT NOT ALL) do capture at 24p and store interlace format. For many reasons. One of them is the limitation of the supported tape format. For example, DV 24p cameras is limited by the DV specifications. CAnon 24f is not actual 24p. It is the CCD doing 48i scan cycle - insted of 24p.
And yes there is 48i in HDV - it is 24f
1. HD can either be 24p or 23.976 on capture. It depends. Varicam for example can be switched to 24p EXACT (seperate crystal). HDCAM also. Most prosumer cameras like DVX200, HVX200 and etc are limited to 23.976.MovieStuff wrote: But does HD 24P capture and play back at exactly 24fps or does it really capture and play back at 23.97fps? Or does HD 24P capture at exactly 24fps and play back at exactly 24fps on a 24P editing NLE but then also plays back at 23.97fps when viewed on NTSC display for broadcast?
Roger
2. Yes. 24p exact would be converted to 23.976p somewhere down the process - like when mastering to tape for delivery. Since all NTSC broadcast standards are all 23.976/29.97/59.94 variants. There is no way to get around .1 NTSC factor for TV transmission.