Avid Technology Pro Tools SYNC HD, Руководство пользователя

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Chapter 4: Using Pro Tools | SYNC HD 33
Video Ref vs. Video in
To ensure constant clock referencing, use
Video Ref input as your clock reference instead of
Video In, whenever possible. When using Video
Ref (and house sync), if the video picture is lost,
the SYNC HD will remain resolved to the black
burst signal at the Video Ref input.
To set VITC as the SYNC HD positional reference
using Pro Tools:

In the
SYNC Setup
section of the Session Setup
window, select
VITC
from the
Positional Refer-
ence
pop-up menu.
To set VITC as the SYNC HD positional reference
using the front panel controls:

Press the Positional Reference switch to select
VITC.
Additional VITC-Related Settings
SYNC HD Settings
Make sure to set the appropri-
ate clock reference, sample rate, frame rate, and
freewheel duration.
Connections and Sources
Make sure that your
VITC-striped video signal, if any, is routed to the
Video In connector (not a Video Ref connector). If
you use a black burst signal as clock reference,
connect it to a Video Ref connector.
We recommend using Video Ref as your Clock
Reference (rather than Video In) when working
with VITC, because a blackburst signal at the
Video Ref input will always be present, unlike the
video signal at Video In, which may disappear.
Auto LTC/VITC Positional
Reference
In Auto LTC/VITC mode, the SYNC HD switches
automatically between LTC and VITC depending
upon which is delivering the best timecode signal.
This is indicated on the front panel by the LTC and
VITC positional reference LEDs (both will be lit),
and by a decimal point between the minutes and
seconds on the front panel timecode display.
VITC cannot be read at high speeds (shuttle
speeds, for example) while LTC can, and LTC can-
not be read at slow speeds (while VITC can be read
at slow speeds, and when parked). Auto
LTC/VITC provides the best of both LTC and
VITC without having to manually switch settings.
Auto LTC/VITC Requirements
• Make sure the LTC signal is routed properly to
the SYNC HD LTC In connector.
• Make sure the VITC-striped video signal is
routed properly to the SYNC HD Video In con-
nector (not a Video Ref connector).
• Make sure to have or stripe matching code on
both your LTC and VITC tracks (and your on-
screen video window burn, if any).
• Make sure to select Auto or the correct line pair
for VITC Read.
• Make sure to select the appropriate clock refer-
ence, sample rate, frame rate, and freewheel du-
ration options.
The Positional Reference setting you choose
remains set, session to session, until it is
changed again.
If the same tape has different values for LTC
and VITC signals, make sure to run only refer-
encing LTC by disabling Auto LTC/VITC. Oth-
erwise, Pro Tools may locate to different
places depending on whether the tape is idle or
playing back.