Blend Modes
While the Opacity parameter defines a uniform level of transparency for a layer, the blend
modes allow you many more creative options to control how the overlapping images
interact, based on the colors in each layer. By default, each layer’s blend mode is set to
Normal, so changes to a layer’s opacity uniformly affect every part of the image equally.
Blend modes can create transparency in a layer regardless of the setting of its Opacity
parameter. This is because the pixels of an image with a selected blend mode are
combined with the pixels of any layers lying immediately below in the Canvas. For example,
if you overlap two layers, then set the blend mode of the top one to Screen, the darker
areas of the screened image become transparent, while the lighter areas remain more
solid, resulting in the following image:
Important:
The transparency created by most of the available blend modes only affects
how a layer combines with overlapping layers underneath. These blend modes do nothing
to affect a layer’s alpha channel. For information about blend modes that do affect a
layer’s alpha channel, see
Blend Modes That Manipulate Alpha Channels
.
Each blend mode combines layers in different ways. For example, setting the top layer’s
blend mode to Multiply yields a result opposite to that of the Screen blend mode, as the
darker areas of the image remain solid, and the lighter areas become transparent.
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Blend modes only affect the combination of a layer with the layers below it. Any layers
appearing above have no effect on this interaction, even if the layer is transparent. In the
following example, the text layers on the top level have no effect on the blended images
below.
For overlapping layers with different blend modes, the bottommost pair of layers is
combined first, and that combination then interacts with the next layer up, and so on
until all overlapping layers are combined for the final image. In this case, each layer with
a specified blend mode only interacts with the image below it, whether that image is a
single layer or a pair of layers blended together.
Each of Motion’s blend modes works in conjunction with the Opacity parameter to alter
the interaction between the foreground and background layers. Adjusting a layer’s opacity
lessens the blending effect assigned to it, even as it reduces that layer’s visibility. This
allows you to customize any blend mode to better suit your needs.
Blend modes only affect overlapping layers, and have no interaction with your project’s
background color (unless the background is set to Environment). If you specify a blend
mode for a layer that doesn’t overlap anything, that layer remains as it was before.
To change a selected layer’s blend mode
Do one of the following:
µ
Choose an option from the Blend Mode pop-up menu in the HUD.
µ
Choose an option from the Blend Mode pop-up menu in the Properties Inspector.
µ
Choose Object > Blend Mode, then choose an option from the submenu.
µ
Display the Blend Mode column in the Layers list (choose View > Layers Columns > Blend
Mode), then choose an option from a layer’s Blend Mode pop-up menu.
µ
Control-click a layer in the Canvas, then choose an option from the Blend Mode submenu
in the shortcut menu.
µ
Control-click a layer in the Layers list or Timeline, then choose an option from the Blend
Mode submenu in the shortcut menu.
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