Manual secondaries are additional secondary flares that are individually added to the lens flare. Manual secondary flares can be used in addition to, or in place of automatic secondary flares.
You can have groups of secondary flares, instead of just one set. Many of the controls in this dialog box are for a specific set of flares, not all sets.
Size: Controls the size, as a percentage of the overall image, of the manual secondary lens flare. This parameter is animatable.
On: Turns manual secondary flares on or off. This option must be on, and the check mark in the Preferences tab must be selected, for the manual secondary flares to render.
Plane: The plane, in degrees, in which the manual secondary flares will appear. This parameter is animatable.
Number: The total number of flares that will appear in the secondary flare plane.
Shape: Controls the overall shape of the secondary flares.
Arrow Buttons: Lets you move between sets of secondary flares easily. The current set name appears to the right of the arrow buttons.
Add Del: Lets you add another set of manual secondary flares to the lens flare.
On: Turns the current set of manual secondary flares on or off.
Axial Fade: Specifies whether or not the current set of secondary flares has axial fade.
Gradients: Defines the gradient for the secondary flare.