5.5

1068Motion User Guide
Light Wrap controls
Click the disclosure triangle in the Light Wrap row to reveal controls for blending color and
lightness values from the background layer of your composite with the keyed foreground
layer. Using these controls, you can simulate the interaction of environmental lighting
with the keyed subject, making it appear as if background light wraps around the edges
of a subject. In Motion, the Light Wrap operation blends light and dark values from the
background with the edges of the keyed foreground subject, and can be used to create
color-mixing effects around the edges of the solid part of a key to better marry the
background and foreground layers of your keyed composite.
Light Wrap is the last operation in the image-processing pipeline. In other words, the light-
wrap effect is added after every other image operation is processed, including filters, lights
and shading, and other composited effects. As a result, Light Wrap accounts for any visual
effect that might alter the look of the object it is applied to, yielding the most desirable
result.
Important: A separate Light Wrap option appears in the Blend Mode pop-up menu of the
Properties Inspector for a selected layer or group in Motion. The Light Wrap blend mode
in the Properties Inspector for a layer is ignored when you add a Keyer filter to that layer
and set the Light Wrap Amount parameter to a value greater than 0. (The Light Wrap
parameters of the Keyer filter take precedence.) However, if you set the Amount parameter
of the Light Wrap group to 0, the Light Wrap blend mode becomes active again. Further,
the Light Wrap blend mode in the Properties Inspector for a group overrides the Light
Wrap parameters of any Keyer filters in that group.
• Amount: A slider to control the light-wrap effect, setting how far into the foreground the
light wrap extends.
• Intensity: A slider to adjust gamma levels to lighten or darken the interaction of wrapped
edge values with the keyed foreground subject.
• Opacity: A slider to fade the light-wrap effect up or down.
• Mode: A this pop-up menu to choose a compositing method to blend the sampled
background values with the edges of the keyed subject. There are five options:
• Normal: Evenly blends light and dark values from the background layer with the
edges of the keyed foreground layer.
• Lighten: Compares overlapping pixels from the foreground and background layers,
then preserves the lighter of the two. Good for creating a selective light-wrap effect.
• Screen: Superimposes lighter portions of the background layer over wrapped areas
of the keyed foreground layer. Good for creating an aggressive light-wrap effect.
• Overlay: Combines the background layer with the wrapped areas of the keyed
foreground layer so overlapping dark portions become darker, light portions become
lighter, and colors become intensified.
• Hard Light: Acts like the Overlay composite mode, except that colors become muted.