Blending Curves with the Alpha Tool

Blend curves are used to adjust the blend of the front and back elements by adjusting the amount of fractional opacity (pixel area) for the front, and one minus front. The latter gives more importance to the back. Blend curves is useful for controlling the blend along the edges of a matte by adjusting fractional values, not 0 and 1 values. Because mattes have fractional values along the edges, the blend curves affect the edge blending.

To blend curves:

1. Select and drag a control point on the curve.

To add a control point to the curve:

1. With the cursor in the curve window, press + (plus sign) and click the curve at the location in which you want to add a control point.

To delete a control point from the curve:

1. With the cursor in the curve window, press - (minus sign) and click the control point you want to delete from the curve.

To remove the Add or Delete control point mode:

1. Press Esc.

To reset a single curve:

1. Select the curve and click Reset.

To reset both curves at the same time:

1. Hold down the Ctrl key and select both curves then select Reset.