User`s guide

Pro Tools Reference Guide336
Final Audio Destination: Film
If your final destination is film, your source
audio is at film speed, and your goal is to
edit and mix audio in Pro Tools and then
lay back to a device that runs at film speed
(such as Mag or Time Code DAT), you can
temporarily Pull Down the audio in
Pro Tools for NTSC video work, then return
the audio back to film speed when you’re
finished.
For example, film speed audio from a Nagra
machine that is referenced to 30 FPS time
code is recorded into your Pro Tools system
at a sample rate of 44.1 or 48 kHz. Keeping
in mind that film speed is faster than video
speed, select 30 FPS in your Session Setup
window in Pro Tools, and record in your
audio online and referenced to the time
code on the Nagra.
Once all the audio has been recorded, and
you are locked to a video work print (at
“video speed”), set up Pull Down. If you are
using a Digidesign USD, SSD, or VSD, select
Pull Down in the Session Setup window.
(You also have to select Pull Down manu-
ally on the front of the VSD.) If your syn-
chronizer is not a Digidesign product, se-
lect Pull Down on the front of your
synchronizer, then enable Pull Down in
the Pro Tools Session Setup Window. At
this point, it is highly recommended that
you verify whether the video you’re work-
ing with is striped with 29.97 Drop Frame
or Non-Drop Frame time code. While in
Pull Down mode, you can work with your
reference video and everything will remain
in sync and run at the proper speed (assum-
ing your system is completely resolved).
Once you are ready to lay back your com-
pleted project to an audio device running
at film speed, deselect Pull Down in the
Session Setup Window, and from your syn-
chronizer if it is not a USD or SSD. Then
change your time code frame rate in the
Pro Tools session back to 30 FPS. Once Pull
Down has been deselected, the audio
played back from Pro Tools will synchro-
nize perfectly with the edited film.
Alternately, you can pull down the source
audio deck while recording audio into
Pro Tools, work at 29.97 FPS with no Pull-
Down selected in Pro Tools, and then
switch to 30 Non-Drop frame format, and
select Pull Up during the delivery stage.
You will have to perform a sample rate con-
version the audio either digitally or by us-
ing an analog stage (D-A-D).
Final Audio Destination: Video
If you are working with video that was
transferred from film, your audio source is
at film speed, and the final layback destina-
tion is NTSC video (or television), and you
would like to provide a digital transfer to
your clients, you will need to alter the
above recipe slightly. Keep in mind that
when you are working in Pull Down mode,
your active sample rate is 44.056 kHz (if the
audio was recorded at 44.1 kHz) or 47.952
kHz (if the audio was recorded at 48 kHz).