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Gogu
06-14-2008, 06:25 AM
Can you tell me is there a difference in terms of "filmic look" between the true 24p that the more expensive cameras can shoot and the 23.98p 23.976p that the EX1 does, or any other camera that does 24p (the HVX for example). As far as i've come to understand the advantage of shooting 23.98 is that you don't have to do all those pulldowns/pullups to convert for NTSC.

And is 23.98 and 23.976 the same thing in terms of editing ? The EX1 has the 23.98 in the 24p NTSC mode and for the 30p NTSC is uses the 23.976!

Is the 23.98 for easier 3:2 pulldown to NTSC ?

Thanks!

csundbom
06-14-2008, 08:34 AM
Yes, 23.976 and 23.98 is the same thing. Digital video cameras use 23.976 instead of 24 for easy transfer to NTSC/HD. Only film cameras use 24 fps. You still have to do pulldown to 59.96 (60Hz) 480i if you intend to distribute on DVD. Bluray can take 23.976 natively, and the pulldown is added by the player as needed, depending on output format.

matthew77
06-14-2008, 08:36 AM
23.98 is the same as 23.976. Just an abbreviation for the same thing (24fps minus 0.1%).

And 30p is actually 29.97fps (30fps minus 0.1%)

There is no visible difference between 23.976 and 24p. It's visually infinitesimal.

Higher end cameras do shoot a true 24p as well as 23.976, but this is based on production and postproduction choices and generally concerns sound sync issues, compatibility with film cameras running at 24p and on-set monitoring (if you are using standard def NTSC monitors, you need to shoot 23.976 to allow for a clean downconversion). It has nothing to do with a desired look.

NTSC runs 29.97fps. This is due to an issue that came up with the introduction of color broadcast television (way back when) where the color signal interfered with the broadcast audio. By slowing down the frame rate slightly, the interference was eliminated. See "History" section here:

http://en.wikipedia.org/wiki/NTSC

23.976 is a derivative of this and allows for simple integer conversion between "24 frame" based material and "30 frame material" (60 field material actually) using 3-2 pulldown and not some higher mathematics that would required otherwise.

For more info (see "2:3 pulldown):

http://en.wikipedia.org/wiki/Telecine

All filmed material shot at 24p or on film at 24fps when broadcast in the US or other NTSC countries is actually played at 23.976fps due to the .1% speed difference inherent to NTSC.

Gogu
06-14-2008, 09:30 PM
thanks guys!

But i read an interesting debate a while ago on the web about the canon HV20 which shoots true 1080p with 24 progressive. The problem was that it was something like 23.98 ?! (i think)....and the conclusion was that you had to do some 20+ steps in FCP to get to the same thing that other cameras do natively, and that the HV20 uses a mockup of 24p and people think this is a great camera as it can shoot 24p...what was that about ?

csundbom
06-15-2008, 09:15 AM
The HV20 stores the 1080/24p (actually 23.98) stream inside a 1080i wrapper, so you need to do pull-up back to true 24p somewhere. It's wastes time and storage if you want to do this is a lossless fashion. But it works.

doofalot
06-16-2008, 04:36 PM
does the ex1 do its 24P at all resolutions including the max 1080x1920?

Barry_Green
06-16-2008, 04:48 PM
The EX1 does 24p at 1920x1080 and at 1280x720. I don't remember if it does 1440x1080 24p; if it does, I'm certain it's contained within a 60i wrapper.

Huy Vu
06-16-2008, 05:11 PM
In 25mbps mode the EX1 records 24p at 1440 x 1080 inside a 60i wrapper.

doofalot
06-16-2008, 09:40 PM
since i'm on that topic, are all the frame rates like 22p, 26p, etc available in full HD mode?

Barry_Green
06-16-2008, 09:41 PM
Depends on what you mean by "full HD". If you mean 1920x1080p, then you get frame rates from 1 to 30. If you allow 1280x720 as full HD, then yes you get all frame rates from 1 to 60.