Tektronix Camcorder 2200 User Manual

2-25

When the key bus is contributing to the switcher Program output, 
pressing

 does not low tally the key bus, even though 

the key fill video is not visible.

Video fill mode operates with background keyers in layered 
mode. When the keyer is delegated to a background layer, the

 button is turned on automatically (

 is 

turned off).

The

 and

 buttons determine the 

source of the key.

Pressing the

 button forces derivation of the key from a 

video source. The “video source” is the video selected on the key 
bus (for keyers 1 and 2) or on the background bus (for background 
keyers in layered mode only).

If 

and

 are both selected, the result is a self-

key.

Pressing

 while in Chroma Key mode causes an 

encoded chroma key, using the fill video as the source for the 
encoded chroma keyer.

Pressing the

 button forces the key to be derived 

from a user-defined source.

User preferences selected in the Configuration/User Preferences 
menu determine whether a luminance or linear key is a self-key or 
an external key (and determine which external key is used). They 
also specify whether chroma keys are encoded or analog 
component (YUV, BETA, MII, or RGB).