Shadow Parameters
The Shadow Parameters rollout is displayed for all light types except Skylight and IES Sky, and for all shadow types. It lets you set shadow colors and other general shadow properties.
Atmospheres and Effects for Lights
The Atmospheres & Effects rollout lets you assign, delete, and set up parameters for atmospheres and rendering effects associated with the light. This rollout appears only in the Modify panel; it doesn't appear at creation time.
Advanced Effects Rollout
The Advanced Effects rollout provides controls that affect how lights affect surfaces, and also includes a number of fine adjustments and setting for projector lights.