Tektronix Grass Valley 3000 - Manual (Page 261)

Using the Super Black Output
C-5
Each output module has four channels that are arranged with the
video and key on adjacent channels. For example, the Program
Output module is arranged as follows:
Channel 3 -> Program Video
Channel 4 -> Program Key
The Configuration/Outputs menu allows you to turn Super Black
on for a particular output.
When Super Black is turned on for the channel 3 output, for
example, the output is:
Channel 3 Output = Program Key (Program Video – Super
Black Value) + Super Black Value.
(The Super Black Value is also a register value on the output
module. It uses the same Super Black Value found in the
System Parameters menu.)
When Super Black is turned off:
Channel 3 Output = Program Video.
This method also allows you to lay up to 8 layers at a time to tape.
Reconstructing the Signal
To reconstruct the video and key:
1. Map the tape machine input with the Super Black source to a
crosspoint.
2. Select that crosspoint as a Key and put the Key on in Video
Key/Lum Key mode.
3. Turn on Chroma Trap (in the Keyer menu).
4. Adjust the Clip and Gains as well as possible on Key panel.
5. Adjust Coring (in the Keyer menu, available only for M/Es).