Setup
First prepare the light source. This is the part of the video image from which the light should shine. To make it easier, enable the Setup control, and then adjust the Light Source parameters to isolate the portion of the picture that will source the glow. Once the Light Source is ready, disable Setup and design the light behavior with the Glow control group. Then, set the Shimmer controls to add random motion to the light. Finally, set the Mix levels.
- The Light Source group sets up the initial intensity and shape of the light glow source.
- Color sets the color of the light source. Typically, this is white, for a bright light. However, it can be any color, light or dark. Colors close in brightness and hue to the chosen color will glow, even if that color is dark. Examples are a white light, blue sky, or a bright red flower.
- Sensitivity sets the strength of the glow source. As the sensitivity is dialed up, more and more of the image becomes part of the glow source.
- Position and Radius define a circle within the image for the light source. This allows you to isolate the area of the image that can generate light.
- Feather sets the smoothness of the light as well as the smoothness of the circle boundary. Increase Feather to reduce the harshness of the light.
- The Glow group sets up the glowing light behavior.
- Color sets the color of the actual glow. Use the color dropper to select a color directly from the video. Or, click on the color swatch to create or edit the color directly.
- Blend determines the blend of the Glow color and original colors.
- Strength sets the strength of the glow. Drag all the way to the left to show just the original image. Drag to the right to increase the intensity of the glow until it becomes a harsh light.
- Width sets the width of the glow. Drag to the right and parts of the picture that glow increasingly shed light over the adjacent image.
- Ambience adjusts how much of the scene is affected. At lower values, only the brightest areas glow, but at higher values, the whole image blooms.
- The Shimmer group sets random noise to make the light flicker and move.
- Size sets the size of the random noise.
- Intensity sets the strength of the shimmer effect.
- Rate sets the speed at which the changing light moves and mutates.
- The Mix group has three controls:
- Liquify distorts the image underneath the light rays, using the light itself to set the shape of the mutation.
- Picture sets the level of the original image displayed under the glow. Note that turning down Picture creates transparency, which can be used to display the glow as an overlay over another track.
- Glow sets the brightness of just the glow.
- Set Up makes it much easier to design the light source. Turn on Set Up, then work on the parameters in the Light Source and Shimmer groups. Once these are ready, disable Set Up.