HD formats, frame sizes and timecodes demystified...
by Greg Nosaty
on
Aug 5, 2009 at 11:24:28 pm
Has anybody on the list either written or come across a "definitive guide" to demystify HD formats, frame sizes and timecodes? A document that would explain things like why DVCPro 720 is 960 x720 (anamorphic) and not 1280 X 720 like the others, or why FCP ingests 24p media as 23.98 if it is a non-drop format...
Re: HD formats, frame sizes and timecodes demystified... by Tom Wolsky on Aug 5, 2009 at 11:32:20 pm
Panasonic uses 960 as a way of compressing the data. The video frame rate for 24p is 23.976. Final Cut calls it 23.98, but it is actually 23.976. Drop frame and non-drop frame has nothing to do with the actual frame rate. It is only how the frames are counted.
All the best,
Tom
Class on Demand DVDs "Complete Training for FCP6," "Basic Training for FCS2" and "Final Cut Express Made Easy"
Author: "Final Cut Pro 5 Editing Essentials" and "Final Cut Express 4 Editing Workshop"
Re: HD formats, frame sizes and timecodes demystified... by Aaron Neitz on Aug 5, 2009 at 11:34:35 pm
nothing i know of. just years of experience.
1)Because Panasonic is cheating HD resolution by using an anamorphic trick. It really is 960 pixels - you gotta strech it out to fit 1280.
2)98% of 24p media is actually 23.976 media, and 98% of workflows should conform to that. DF and NDF are simply counting methods. They don't affect the amount of frames
Re: HD formats, frame sizes and timecodes demystified... by Shane Ross on Aug 5, 2009 at 11:53:49 pm
[Aaron Neitz]"1)Because Panasonic is cheating HD resolution by using an anamorphic trick. It really is 960 pixels - you gotta strech it out to fit 1280. "
MOST formats "cheat" their resolution. HDV is 1440x1080...not full 1920x1080. JVC HDV is 960x720. A majority of HD tape formats are anamorphic. That is how they compress the footage to save space.
[Aaron Neitz]"DF and NDF are simply counting methods. They don't affect the amount of frames "
True, but they sure mess with getting proper show times...ACTUAL length of a show. NDF isn't time accurate, DF is.
Re: HD formats, frame sizes and timecodes demystified... by Tom Wolsky on Aug 6, 2009 at 12:02:19 am
"JVC HDV is 960x720"
Unless this has changed JVC shoots full 1280x720. I think only DVCPRO HD shoots 960x720. Who knows, there's going to be another format next week anyway.
All the best,
Tom
Class on Demand DVDs "Complete Training for FCP6," "Basic Training for FCS2" and "Final Cut Express Made Easy"
Author: "Final Cut Pro 5 Editing Essentials" and "Final Cut Express 4 Editing Workshop"
Re: HD formats, frame sizes and timecodes demystified... by Tom Wolsky on Aug 6, 2009 at 12:38:28 am
Long GOP MPEG-2 that's the one.
All the best,
Tom
Class on Demand DVDs "Complete Training for FCP6," "Basic Training for FCS2" and "Final Cut Express Made Easy"
Author: "Final Cut Pro 5 Editing Essentials" and "Final Cut Express 4 Editing Workshop"
Re: HD formats, frame sizes and timecodes demystified... by Greg Nosaty on Aug 6, 2009 at 12:29:53 am
Shane, thanks for the link to Phil Hodgetts.
Here is graphics questions to go with the anamorphic HD formats. Say you were going to make graphics for a project shot in HDV would you work in 1440x1080 rectangular pixels or 1920x1080 square pixels? Or a DVCPro 720p project would you work in 960 x 720 rectangular pixels or 1080 x 720 square pixels? Presuming we are importing and editing in FCP.
Re: HD formats, frame sizes and timecodes demystified... by Greg Nosaty on Aug 6, 2009 at 3:41:27 am
Thanks Aaron
What I'm really I'm looking for a book or PDF not comments. I want something that I can pass on to new assistants, PA's and the like who ask me these kinds of questions every day.
[Aaron Neitz]"2)98% of 24p media is actually 23.976 media, and 98% of workflows should conform to that. DF and NDF are simply counting methods. They don't affect the amount of frames "
HD formats, there's PAL here too by Neil Sadwelkar on Aug 6, 2009 at 4:18:32 am
[Aaron Neitz]"98% of 24p media is actually 23.976 media, and 98% of workflows should conform to that."
Hang on a minute. In many NTSC countries, a large part of HD media at 24fps is expressed as 23.976. But where did the 98% come from? 98% of all media in NTSC countries, or worldwide?
In the PAL world, we have no use whatsoever of 23.976. Film (as film everywhere) runs at exactly 24fps. And when we make that out for HD tape, we make a 1080p24 tape.
When one makes a ProRes Seq at 24fps, Apple FCP, 'helpfully' sets it as it 23.976. We 'respectfully' change that to 24fps and make a HD master.
When run out to PAL Digibeta this is transferred at 25fps for PAL TV. And when shown on a HDTV station, its shown at 24fps. We don't do any thing at 23.976, unless we have to send it to the US. Which is not 98% of the time.
So, 24 fps is probably not 23.976 fps, 98% of the time and 98% of workflows need not conform to that.
I'm bringing this up because budding editors in PAL world where this forum is visible, often mistakenly set things up for 23.976 which causes serious headaches when inter-working with ProTools and unimaginable sound sync issues. Especially because the difference between 23.976 and 24 is so small but it becomes an issue if you have films about 3 hrs long.
So if anyone is doing 24 in a PAL country, it should be 24 all along.
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Neil Sadwelkar
neilsadwelkar.blogspot.com
twitter: fcpguru
FCP Editor, Edit systems consultant
Mumbai India
