DigiDesign SYNC HD, Руководство пользователя

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Chapter 4: Using SYNC HD 45
Clock Considerations for VITC
To avoid tape protection mode problems and
ensure constant clock referencing, use the Video
Ref In as your clock reference instead of Video
In, whenever possible. When using Video Ref In
(and house sync), if the video picture disappears
the SYNC HD will remain resolved to the black
burst signal at the Video Ref In connector.
To use VITC as the SYNC HD positional reference:
From Pro Tools:
„
In the SYNC Setup section of the Session
Setup window, select VITC from the Positional
Reference pop-up menu.
From the front panel:
„
Press the Positional Reference switch to select
VITC.
From the SYNC Setup software utility
(Windows only):
„
Select Vertical Interval Time Code (VITC)
from the SYNC Setup Positional Ref pop-up
menu.
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
SYNC HD Video In connector (not the Video Ref
In connector). If you use a black burst signal as
clock reference connect it to the Video Ref In
connector.
You should consider using Video Ref as your
Clock Reference (rather than Video In) when
working with VITC because a black-burst signal
at the Video Ref input will always be there, un-
like the video signal at Video In, which may dis-
appear if the videotape disengages.
Auto Switch LTC/VITC Positional
Reference
In Auto Switch mode, the SYNC HD switches
automatically between LTC and VITC depend-
ing upon which is delivering the best time code
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 be-
tween the minutes and seconds. on the front
panel time code display.
VITC cannot be read at high speeds (shuttle
speeds, for example) while LTC can, and LTC
cannot be read at slow speeds (while VITC can
be read at slow speeds, and when parked). Auto
Switch LTC/VITC provides the best of both LTC
and VITC reading without having to manually
switch settings.
Auto Switch 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
connector (not the Video Ref In 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 ref-
erence, sample rate, frame rate, and freewheel
duration options.