What it does: Light Rays simulates a bright light source that casts beams of light through the video image. It streams light from bright spots of the image and expertly produces compelling and atmospheric looks, such as a heavenly glow shimmering through clouds, bright titles breaking through fog and rays of light in a dark scene.
How to use it: 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 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 radiate light rays, even if that color is dark. Examples are a white light, blue sky, or a bright red flower.
- Sensitivity sets the strength of the light source. As the sensitivity is dialed up, more and more of the image becomes part of the light 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 a 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 Light Rays group sets up the color and shape of the light rays emanating from the image.
- Bright Shade and Dark Shade set the two colors for the light parts of the light rays and dark parts. However, note that these color are only used if Mix Shades is set correctly.
- Mix Shade sets the blend between light rays that use the original image colors and light rays painted with the Bright and Dark shade colors.
- Angle and Length set the direction and length of the light rays. Angle represents the source location of the light so the rays will extend the opposite direction.
- The Shimmer group sets random noise to make the light rays 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 rays themselves to set the shape of the mutation.
- Picture sets the level of the original image displayed under the rays. Note that turning down Picture creates transparency, which can be used to display the light rays as an overlay over another track.
- Rays sets the brightness of just the light rays.
- 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.