Apple Final Cut Pro 7 - Manual (Page 1403)

Using information from the Video Scopes tab, you can adjust the Whites and Mids sliders
to make the two spikes of the Histogram match more closely, so you get comparable
luma levels. Moving one invariably results in some movement in the other, but keep
making your adjustments until the Histogram for the second shot approximates the
Histogram for the first shot.
8 With this accomplished, focus on the RGB Parade scope. It shows that the second clip
has far more blue and green than the first.
Second clip First clip
Adding progressively more cyan to the midtones brings the hues of the two shots closer
to one another. As you adjust the Mids control, continue comparing the previous shot
and the current shot as outlined in step 7. Continue to make adjustments until the shots
match as closely as you need them to.
Note: Remember that your goal, in this case, is to balance all the shots in the scene so
that as the sequence plays, no one shot stands out from any of the others.
1403 Chapter 82 Color Correction Examples