You can interactively adjust the attributes of lights in the Scene View using light gizmos. 
The light, which is represented by a light glyph, can be repositioned after it is placed in the model. To activate a light gizmo, you need to select a light either in the Scene View or on the Lighting tab, the Lights view. 
With the light gizmos you can: 
- Move the location (origin) of the light. All lights include this option. 
 
-  Move the hotspot angle. Only the spot light includes this option. 
 
- Move the falloff angle. Only the spot light includes this option. 
 
- Move the target of the light. Spot lights, web lights, and distant lights include this option.