Apple Color 1.0 - Manual (Page 183)

Chapter 9 Primary In 183
Understanding Shadow, Midtone, and Highlight Adjustments
Like many other color correction environments, Color provides a set of three color
balance controls for the specific adjustment of color that falls within each of three
overlapping zones of image tonality. These tonal zones are the shadows, midtones, and
highlights of the image, which were covered in the previous section on contrast. If you
were to reduce the tonality of an image into these three zones, it might look
something like the following illustration.
Three-zone controls allow you to make targeted adjustments to the color that falls
within the highlights of an image, without affecting color in the shadows. Similarly,
they allow you to make separate adjustments to differently lit portions of the image to
either make corrections or achieve stylized looks.
Original color image Simulated tonal zones, shadows, midtones, and
highlights
Areas most affected by the Midtone color
balance control Areas most affected by the Shadow color
balance controlmidtones using the Luma curve
Areas most affected by the Highlight color balance control