Apple Color 1.0 - Manual (Page 193)

Chapter 9 Primary In 193
To remove control points from a curve:
m Drag a point up or down until it’s outside the curve control area.
To remove all control points from a curve:
m Click the reset button (at the upper left-hand side of each curve graph) for the curve
you want to clear control points from.
Using Curves to Adjust Contrast
One of the most easily understood ways of using curves is to adjust contrast with the
Luma curve. The Luma curve actually performs a simultaneous adjustment to the red,
green, and blue channels of the image (as you can see if you take a look at the Parade
scope while making Luma curve adjustments), so the overall effect is to adjust the
lightness of the image.
Note: Adjustments made to the Luma curve may affect its saturation. Raising luma by a
significant amount can reduce its saturation.
You can draw a general correspondence between the controls described previously in
“
Using the Primary Contrast Controls ” and the black point, midtones, and white point
of the Luma curve. For example, moving the black point of the curve up raises the
black point.
Moving the white point of the curve down lowers the white point of the image.