Help understanding 24, 24p, 23.98 and 23.98sf

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Help understanding 24, 24p, 23.98 and 23.98sf

Postby pablobw on 04/16/2014, 11:16 am


I would really like to understand the difference of this terms.

I know that DCPs are made at True 24fps. And i think i understand that 24p is actually 23.98 (i don't know why though)

But i would like a cristal clear explanation of this 4 terms, so i don't use them incorrectly and so i can make all my deliveries just like they should be.

Thanks in advance.
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Joined: 04/16/2014, 11:09 am

Re: Help understanding 24, 24p, 23.98 and 23.98sf

Postby thekodols on 04/16/2014, 1:47 pm

p - progressive
i - interlaced
sf - segmented frames

sf (or psf, progressive segmented frames) means that frames are stored as two fields that are recombined during playback into p frames. 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. Except for rare cases, you don't have to even know about this.

24p is 24 progressive frames per second. Cinema standard.
23.98p is 23.98 progressive frames per second. NTSC TV standard.

24 is different from 23.98, p or no p.

There are cameras that shoot 24p, there are cameras that shoot 23.98p, there are cameras that say they shoot 24p NTSC which means 23.98p and some that assume that 24p is 23.98p, but technically 24p is not the same as 23.98p.
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Re: Help understanding 24, 24p, 23.98 and 23.98sf

Postby al board on 04/17/2014, 1:49 am

al board
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Joined: 05/3/2010, 5:22 am

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