User`s guide

Chapter 24: Time Code Synchronization 343
Variable Speed Override
Variable Speed Override (VSO) requires a
USD (or SSD). When a USD is connected to
Pro Tools, the Session Setup window ex-
pands to display additional controls for
VSO, clock, and Positional Reference (see
Figure 23).
Refer to the Universal Slave Driver User's
Guide for instructions on using VSO to
varispeed Pro Tools playback.
Preparing to Work with
SMPTE
The first step when preparing to work with
SMPTE is to choose an appropriate SMPTE
frame rate.
SMPTE Formats
Pro Tools supports all standard SMPTE
frame rates. For a full explanation of these
SMPTE frame rates, see “SMPTE Frame For-
mats” on page 332.
Determining SMPTE Frame Rate
Of course, it’s always best to determine the
SMPTE frame rate through labeling proce-
dures or communication, but this is not al-
ways possible.
If you do not know the frame rate of a tape,
the SSD and USD show incoming frame
rate on their front panel LED indicators.
These devices cannot distinguish between
29.97 fps and 30 fps, but they can deter-
mine whether the incoming frame rate is
drop frame or non-drop frame. With NTSC
video, the frame rate is most likely 29.97
fps Drop or 29.97 fps Non-Drop.
Configuring Pro Tools for
SMPTE
✽ MachineControl is supported on TDM sys-
tems only.
Synchronization and MachineControl™
system parameters are set in the Pro Tools
Peripherals dialog box. These parameters,
such as sync peripheral setups, MIDI Ma-
chine Control, MachineControl, and ma-
chine pre-roll, are system settings, and re-
main constant regardless of the particular
session you are working on.
Other parameters, which are configured in
the Session Setup Window, such as the ses-
sion frame rate, the session start frame, and
time display format, are session-specific pa-
rameters. These parameters can only be
configured when a session is open.
Figure 23. Session Setup window with USD