Adobe AFTER EFFECTS 7.0 Manual page 447

Adjust the following controls for Advanced Lightning:
Changes the path of the lightning.
Conductivity State
These controls adjust various characteristics of the lightning's core.
Core Settings
These controls adjust the lightning's glow.
Glow Settings
Note: To disable the glow, set Glow Opacity to 0. This setting can speed up rendering time significantly.
Specifies the influence of the original layer's alpha channel on the path of the lightning. The
Alpha Obstacle
lightning attempts to wrap itself around opaque areas of the layer's alpha channel, seeing them as an obstacle.
Note: If Alpha Obstacles is set to a value other than 0, it's not always possible to preview the correct result in less than
full resolution; full resolution may reveal new obstacles. Be sure to check the result in full resolution before final
rendering.
Specifies the amount of turbulence in the lightning path. Higher values result in a more complex strike
Turbulence
containing more branches and forks, and lower values produce simpler strikes with fewer branches.
Specifies what percentage of a branch is forked. Its value is influenced by Turbulence and Alpha Obstacle
Forking
settings.
Specifies the amount of continuous decay or dissipation of the lightning strength and influences where the
Decay
opacity of the forks begins to fade.
Decays the main core along with its forks.
Decay Main Core
Composites the lightning with the original layer using the Add blending mode. When deselected,
Add To Original
only the lightning is visible.
Specifies the characteristics of the lightning.
Lightning Type
Note: The type determines the nature of the Direction/Outer Radius contextual control. In the Breaking type, the
branches are focused toward the Direction point as the distance between Origin and Direction increases.
Specifies the point of origin for the lightning.
Origin
This control changes depending on the Lightning Type:
Direction, Outer Radius
•
Is available only when Vertical isn't selected.
Not In Use
•
Specifies the distance that the lightning travels from its origin. It is enabled when Omni or
Outer Radius
Anywhere is selected as the lightning type. Use this control to terminate the lightning at a defined distance from the
origin.
•
Specifies the direction that the lightning will travel. It is enabled when any of the following lightning
Direction
types are selected: Direction, Strike, Breaking, Bouncy, and Two-Way Strike.
Specifies the complexity of the turbulence in the lightning.
Complexity
Specifies the minimum pixel distance between new forks. Lower values create more forks in the
Min. Fork distance
lightning. Higher values result in fewer forks.
Specifies the level at which a path terminates, based on resistance in the atmosphere and
Termination Threshold
possible alpha collision. At lower values, the path terminates more easily when encountering resistance or alpha
obstacles. At higher values, the path more persistently moves around alpha obstacles.
Note: Increasing Turbulence or Complexity values causes resistance to increase in some areas. These areas change as
conductivity changes. Increasing the Alpha Obstacle value causes resistance to increase at alpha edges.
ADOBE AFTER EFFECTS 7.0 441
User Guide