Output to Blu-ray&Projector: why use 23.98fps? at DVinfo.net

Go Back   DV Info Net > Apple / Mac Post Production Solutions > Final Cut Suite

Final Cut Suite
Discussing the editing of all formats with FCS, FCP, FCE


Reply
 
Thread Tools Search this Thread
Old March 16th, 2008, 08:37 AM   #1
Regular Crew
 
Join Date: Jan 2007
Location: Austin, TX
Posts: 157
Output to Blu-ray&Projector: why use 23.98fps?

I'm shooting in Canon's 24f, if my final output is going to be to blu-ray and a progressive digital projector which can both display 24fps - other than being able to monitor on an external ntsc display is there any point in editing in a 23.98 timeline over a straight 24fps timeline?

Last edited by Cal Bickford; March 16th, 2008 at 01:27 PM.
Cal Bickford is offline   Reply With Quote
Old March 16th, 2008, 02:32 PM   #2
Major Player
 
Join Date: May 2006
Location: Toronto ON Canada
Posts: 731
Quote:
Originally Posted by Cal Bickford View Post
I'm shooting in Canon's 24f, if my final output is going to be to blu-ray and a progressive digital projector which can both display 24fps - other than being able to monitor on an external ntsc display is there any point in editing in a 23.98 timeline over a straight 24fps timeline?
Because, IIANM, your footage is really 23.98, not 24 fps. When we're discussing many video cameras (DV, HDV and HD) that shoot "24", we are really rounding up from 23.98. Such is the case with your Canon, I believe.
__________________
Mike Barber
"I'm laughing to stop myself from screaming."
Mike Barber is offline   Reply With Quote
Old March 16th, 2008, 02:42 PM   #3
Regular Crew
 
Join Date: Jan 2007
Location: Austin, TX
Posts: 157
So is Blu-ray's native framerate 23.98 then? I thought this was the frame-rate used on standard interlaced dvds while hd/blu-ray used 24fps...?
Cal Bickford is offline   Reply With Quote
Old March 16th, 2008, 02:56 PM   #4
Major Player
 
Join Date: May 2006
Location: Toronto ON Canada
Posts: 731
Quote:
Originally Posted by Cal Bickford View Post
So is Blu-ray's native framerate 23.98 then?
This is what it says in the official whitepaper (page 17, table 3.3):

"Video streams shall be MPEG-2 video format (ISO/IEC 13818-2) compliant, MPEG-4 AVC video format (ISO/IEC 14496-10) compliant or SMPTE VC-1 video format compliant.

The video formats shown in Figure 3-3 can be used for BD-ROM video streams.

[... for HD:]

1920x1080x59.94-i, 50-i (16:9)
1920x1080x24-p, 23.976-p (16:9)
1440x1080x59.94-i, 50-i (16:9) MPEG-4 AVC / SMPTE VC-1 only
1440x1080x24-p, 23.976-p (16:9) MPEG-4 AVC / SMPTE VC-1 only
1280x720x59.94-p, 50-p (16:9)
1280x720x24-p, 23.976-p (16:9)"

You could pullup your footage from 23.98 to 24.00... but then you may have audio issues to address. Is it worth the effort? That's your call.
__________________
Mike Barber
"I'm laughing to stop myself from screaming."

Last edited by Mike Barber; March 16th, 2008 at 07:54 PM. Reason: correcting URL code
Mike Barber is offline   Reply With Quote
Old March 16th, 2008, 04:00 PM   #5
Regular Crew
 
Join Date: Jan 2007
Location: Austin, TX
Posts: 157
great info thanks Mike! So it looks like Blu-ray does support 23.98fps - This is completely backward from what I thought initially. So where would the advantage be in editing in a 24fps over a 23.8fps timeline other than the ability to sync to a drop frame timecode? Is there any?
Cal Bickford is offline   Reply With Quote
Old March 16th, 2008, 07:54 PM   #6
Major Player
 
Join Date: May 2006
Location: Toronto ON Canada
Posts: 731
Quote:
Originally Posted by Cal Bickford View Post
great info thanks Mike! So it looks like Blu-ray does support 23.98fps - This is completely backward from what I thought initially. So where would the advantage be in editing in a 24fps over a 23.8fps timeline other than the ability to sync to a drop frame timecode? Is there any?
IIRC, there are higher grade cams (VariCam, Viper, etc... not absolute certainty which) that do record 24fps (as in 24.00), so you would want to edit on a 24fps timeline, not a 23.98fps timeline.

I understand why people like to round up and speak of 23.98 as 24 -- it rolls of the tongue much smoother than 23.98 -- however it does easily lend itself to confusion since there is a difference between 23.98fps and 24fps. In the printed world, i wish people would just stick to saying 23.98 and not 24, when it is really 23.98 -- even if it means an extra three keystrokes (and I will readily admit to having done this myself, though I try to make a conscious effort not to). ;-}p

Perhaps I'm too knit-picky about technical clarity... I did get somewhat jumped on once for pointing out that 1920x1080 and 2k are not the same thing (sure they're close, but they are different). I just think there is already enough headiness when it comes to the technical that we don't need to add to it with lazy communication.
__________________
Mike Barber
"I'm laughing to stop myself from screaming."
Mike Barber is offline   Reply With Quote
Old March 16th, 2008, 10:27 PM   #7
Regular Crew
 
Join Date: Jan 2007
Location: Austin, TX
Posts: 157
I agree - there is an amazing amount of technical information that can be absorbed on the internet, it just seems that you have to spend most of your time sorting out the misinformation. Anyways, thanks for helping me clear this up!
Cal Bickford is offline   Reply
Reply

DV Info Net refers all where-to-buy and where-to-rent questions exclusively to these trusted full line dealers and rental houses...

Professional Video
(800) 833-4801
Portland, OR

B&H Photo Video
(866) 521-7381
New York, NY

Z.G.C.
(973) 335-4460
Mountain Lakes, NJ

Abel Cine Tech
(888) 700-4416
N.Y. NY & L.A. CA

Precision Camera
(800) 677-1023
Austin, TX

DV Info Net also encourages you to support local businesses and buy from an authorized dealer in your neighborhood.
  You are here: DV Info Net > Apple / Mac Post Production Solutions > Final Cut Suite

Thread Tools Search this Thread
Search this Thread:

Advanced Search

 



Google
 

All times are GMT -6. The time now is 12:36 AM.


DV Info Net -- Real Names, Real People, Real Info!
1998-2017 The Digital Video Information Network