Tektronix Grass Valley 3000 - Manual (Page 239)

Installation Considerations
A-17
Since the M/E keyers produce shaped video, GVG
recommends the use of the Effects Send option for
communicating between these switchers and Kaleidoscope.
You should also use Aux Bus 1 through 4 (1 and 2 on 2200)
switcher outputs to feed Kaleidoscope.
Even without the Effects Send option, the 4000 and 2200 can
communicate with Kaleidoscope using component digital
interconnects between them via serializers and deserializers.
For the Model 3000, however, the interconnects to
Kaleidoscope must be analog, since Kaleidoscope does not
have composite digital inputs and outputs. Therefore the
unshaper circuits on the Effects Send board are required for
proper communication (unshaping the Model 3000 outputs
for the Kaleidoscope analog inputs).
NOTE: Some devices claim to produce shaped video, but don't. Their
video output contains background signal in the critical soft edges or in
translucent areas. With such devices, the system designer must
determine if properly shaped video exists. If not, an incompatibility exists
and a compromise is required.
One thing that can be done is to set up the device to place foreground
objects over a
black background. In this case, the fill video may be
considered to be shaped .