Re: wav file import to AVID...again


"Phillip W. Palmer, CAS" <phil@xxxxxxxxxxxxxxx> wrote in message
news:1188334812.087319.236210@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Okay... we've gone through this a few times, so I'm sorry. But this
time I'm in the world of HD and 23.97.

The facts: HD cameras filming at 23.97. I record sound at 48K/
29.97. We sync everything in Telecine just fine. The Telecine
session is a 1:1 transfer, no pull downs or anything. No
complaints...everything is fine.

The problem: When importing files directly into the AVID, iso tracks
and whatever, the AVID native sample rate seems to be 47952 (???).
This causes my original files to play fast, more samples. They will
slowly drift out of sync.

I don't want to change my original files in any way, as they are
working fine through Telecine and the post sound process. I still
want to import files into the AVID when needed. What's the workaround
for this issue? Is there a way to import the files and make this
work?

Thanks everyone,
PWP
www.palmeraudio.net


This dosent make much sense. I think that if their AVID Project is a 23.976p
NTSC project it should have sound at 48k with no pull down from the injested
tapes. Perhaps they did not use the proper project rate: If they use a Film
type project that expects telecine from 24 Frame Film that has been pulled
down to 23.976 then I would see how the audio may not stay in sync. However
with the NTSC type project everything should stay in sync at 23.976 48k or
29.97 48K

---Courtney
Here is the text from the AVID website:

Planning a 23.976p NTSC Project

Avid editing systems that include 24p support include a 23.976p NTSC project
type. This

project type is especially designed for capture and output of digital audio
that has been

transferred or recorded at 48 kHz, in sync with picture at 23.976 fps. A
23.976p project lets

you maintain digital standards for all NTSC input and output at 23.976 fps.

Select this project type for one of the following reasons:

.. Your film and audio sources have been synced in the telecine process and
transferred to

digital videotape formats.

.. Your audio and video sources have been shot at a camera rate of 23.976
fps. This rate is

used for film (film-based television) or 24p HD video (television or feature
film). These

sources can be downconverted to standard NTSC without further audio
slowdown.

Audio recorded at 48 kHz can remain at 48 kHz throughout the project.

NOTE: The 23.976 fps frame rate is sometimes referred to as 23.97 fps or
23.98 fps. The 23.976 fps

frame rate is in direct proportion to the NTSC broadcast frame rate of
29.97fps, which is

used for film-to-tape transfer to the Avid editing system.



Limitations for 23.976p Projects

You should be aware of the following limitations when you are planning a
23.976p project:

.. For film projects shot at 24 fps, audio must be "pulled down" or "slowed
down" before

it can be captured into a 23.976p project. The user does not have the choice
of capturing

non-pulled-down audio. Unlike 24p NTSC projects, where the audio pulldown
switch

can be set to 1.0 or 0.99 to support either 24 fps or 23.976 fps, 23.976p
projects do not

use the audio pulldown switch. These 23.976p projects can only support 48
kHz audio

that is in sync with 23.976-fps picture on a 29.97-fps transfer tape.



.. Media created in 24p projects and media created in 23.976p projects are
not compatible.

If you start working in one type of project and then decide to switch to the
other, you

need to recapture all video and audio media. You cannot relink video media
or audio

media across the two project types.



.. OMF and AAF files that are output from a 23.976p project look slightly
different from those

from a 24p project. The edit rates will show up as 23.976 fps in these
files.


.

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  • Re: wav file import to AVID...again
    ... Our dailies tape from Telecine comes in at 29.97. ... where it imports the audio at 47952. ... made from 24 FPS film that has been slowed .1% to 23.976 and had it's audio ... me started on the accuracy of .1% pull up vs. .1% pull down. ...
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