Tektronix Grass Valley 3000, User Manual

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Section 2 — Startup & Configuration
Operating Notes
Field Dominance Selection
In the Model 3000 Switcher, all “set” changes such as crosspoint
selections and E-MEM recalls take effect during the vertical
interval of the video signal, just prior to either Field 1 or Field 2.
The Field Dominance feature in the Configuration/System
Parameters Menu allows you to specify when these changes will
take effect.
1. Press the
CONFG
button on the main menu subpanel, then
press the
SYSTEM PARAMS>
soft button in the Configuration
Menu. This will bring up the System Parameters Menu.
With Field Dominance off (
FIELD DOM
set to
NONE
), selection
changes become effective at the beginning of the next field
(immediately after the functions have been changed).
Use of Field Dominance
If the output of the Model 3000 is going to be recorded onto tape
that will later be edited along with other tape, it is important that
changes take place consistently on the same field. They can occur
on either Field 1 or Field 2 of the frame, but need to be on the same
field every time. If this is not done, there will be a “flash” at the
edit in the resulting taped video.
With
FIELD 1
selected as the dominant field, if a change takes place
just prior to Field 1, the change will become effective at the
beginning of Field 1. But if the change takes place prior to Field 2,
the change will be delayed by one field so that it also becomes
effective at the beginning of the next Field 1. This way, all changes
will be synchronized to take place at the beginning of Field 1.
Similarly, if
FIELD 2
were selected as the dominant field, those
changes that take place prior to Field 1 would be delayed until
Field 2.