Apple Color 1.0 - Manual (Page 159)

Chapter 8 Video Scopes 159
In this way, darker colors lie at the bottom of the interior, while lighter colors lie at the
top. More saturated colors lie closer to the outer sides of the shape, while less saturated
colors fall closer to the center of the interior.
Y’C
B
C
R
The Y´C
B
C
R
color space is similar to the HSL color space, except that the outer boundary
of saturation is represented with a specifically shaped six-sided construct that shows
the general boundaries of color in broadcast video.
The outer boundary does not identify the broadcast-legal limits of video, but it does
illustrate the general range of color that’s available. For example, the following image
has illegal saturation and brightness.
If you turn on the Broadcast Safe settings, the distribution of color throughout the
Y´C
B
C
R
color space becomes constricted.