Click the control or press F to activate.
The Outer Edge Falloff control, part of the Ring Flare control group, sets the rate at which the intensity of the outer edge of the Ring Flare decreases. The outer edge is that portion of the effect that extends outward from the ring.
Higher Outer Edge Falloff values make the intensity of the outer edge fall off more rapidly.
Note that, as the falloff is increased, a point will be reached where the outer edge flare will start to appear smaller. This occurs because the falloff setting has reduced the intensity at the outer edge to a level that is too dim to be visible at the current setting of the Intensity control.