User Guide

CHAPTER 7
258
Working with Masks and Transparency
Subtract Subtracts the mask from all masks located above it in the Timeline window. The
contents of the subtracted mask area display as a hole in the Composition window. This
option is useful when you want to create the appearance of a hole in the center of another
mask.
Intersect Adds the mask to all masks above it, but displays in the Composition window
only the area where the selected mask and any of the previous masks intersect. Where
multiple masks intersect, the opacity of all intersecting masks is added together.
Lighten Adds the mask to all the masks above it, displaying contents of all masked areas
in the Composition. Where multiple masks intersect, the highest opacity value is used, so
opacity doesn’t build up.
Darken Adds the mask to all masks above it, but displays in the Composition window only
the area where the selected mask and any of the others intersect. Where multiple masks
intersect, the highest transparency value is used, so transparency doesn’t build up.
Difference Adds the selected mask to the masks above it, and displays in the Composition
window the mask contents of all masked areas except those areas where the masks
intersect.
To apply a mask mode:
1 In the Timeline window, select the layer containing the mask to which you want to
apply a mode and press M.
2 Click the menu next to the mask name and choose a mask mode.
Modifying multiple masks
If you have selected several masks, you can lock, unlock, invert, or change the modes of all
of the selected masks at once. The choice you make for one mask is applied to all the masks.
To modify several masks at once:
1 Select the masks you want to modify. See “Selecting masks and control points” on
page 244.
2 Select a mask mode; or lock, unlock, or invert one layer’s mask.
UG.book Page 258 Wednesday, February 21, 2001 12:05 PM