Apple Color 1.0 - Manual (Page 181)

Chapter 9 Primary In 181
In the previous example, the image has a red color cast in the highlights, which can be
confirmed by the height of the top of the red channel in the Parade scope.
To correct this, you need to simultaneously lower the red channel and raise the blue
channel, which you can do by dragging the highlight color balance control. The easy
way to remember how to make a correction of this nature is to drag the color balance
control handle toward the secondary of the color that’s too strong. In this case, the
color cast is a reddish/orange, so dragging the color control in the opposite direction,
toward bluish/cyan, rebalances the color channels in the appropriate manner. The
Midtone color balance control is used because the majority of the image that’s being
adjusted lies between 80 and 20 percent.
If you watch the Parade scope while you make this change, you can see the color
channels being rebalanced, while you also observe the correction affecting the image
on your broadcast display.