Adobe AFTER EFFECTS 7.0 Manual page 269

ADOBE AFTER EFFECTS 7.0 263
User Guide
Enhances the contrast of the underlying layer that is visible beneath a mask on the source layer. The mask
Hard Mix
size determines the contrasted area; the inverted source layer determines the center of the contrasted area.
Looks at the color information in each layer and subtracts either the underlying color from the original
Difference
layer color or the original layer color from the underlying color, depending on which has the greater brightness value.
Pure white inverts the original layer color values; black produces no change. This mode is the same as the Difference
blending mode in Photoshop.
The Difference mode from After Effects 5.0 and earlier, renamed Classic Difference. Use it to
Classic Difference
preserve compatibility with older projects; otherwise, use Difference. Classic Difference subtracts the channel values
of the layer and underlying colors and displays the absolute value of the result.
Creates a result similar to but lower in contrast than the Difference mode. Blending with white inverts the
Exclusion
underlying color values. Blending with black produces no change.
Creates resulting colors with the luminance and saturation of the underlying colors and the hue of the layer
Hue
colors.
Creates resulting colors with the luminance and hue of the underlying colors and the saturation of the
Saturation
layer colors. If you use this mode with a layer having no saturation (gray), there is no change.
Creates resulting colors with the luminance of the underlying colors and the hue and saturation of the layer
Color
colors. This preserves the gray levels in the image.
Creates resulting colors with the hue and saturation of the underlying colors and the luminance of the
Luminosity
layer colors. This mode is the inverse of the Color mode.
Creates a stencil using the layer's alpha channel.
Stencil Alpha
Creates a stencil using the layer's luma values. The lighter pixels of the layer are more opaque than the
Stencil Luma
darker pixels.
Creates a stencil using the layer's alpha channel.
Silhouette Alpha
Creates a silhouette using the layer's luma values. The lighter pixels of the layer are more trans-
Silhouette Luma
parent than the darker pixels.
Composites layers normally, but adds complementary alpha channels together to create a seamless area
Alpha Add
of transparency. Useful for removing visible edges from two alpha channels that are inverted relative to each other
or from the alpha channel edges of two touching layers that are being animated.
Prevents clipping of color values that exceed the alpha channel value after compositing by
Luminescent Premul
adding them to the composition. Useful for compositing rendered lens or light effects (such as lens flare) from
footage with premultiplied alpha channels. May also improve results when compositing footage from other manufac-
turers' matting software. When applying this mode, you may get the best results by changing interpretation of the
premultiplied-alpha source footage to straight alpha.
To use stencil and silhouette blending modes
The stencil and silhouette blending modes use either a layer's alpha channel or its luma values to affect the alpha
channel of all layers beneath the layer. This differs from the track matte, which affects only one layer.
The stencil and silhouette blending modes affect all layers below the layer to which they are applied. Stencil mode
cuts through all layers, so you can show multiple layers through the frame of the stencil layer's alpha channel.
Silhouette mode blocks out all layers below it, so you can cut a hole through several layers at once. To keep the
silhouette and stencil blending modes from cutting through or blocking all layers underneath, nest the layer in a
composition.