Check out this demonstrational video to learn how to create lighting FX and fog behind the back of a tombstone that's a great prop for Halloween sets.
The idea is to combat wind and create atmosphere by letting the fog hit the back of the tombstone to collect in an area, then be backlit by the lights.
Using a 400W fog machine with a timer positioned within 1-2 feet of the back of a large tombstone, place the 1000W halogen white balanced floodlights plugged into a Lightning FX unit behind the setup.
One problem with the Lightning FX unit is that it was controlled by sounds from a CD player. The passing cars and the fog machine sounds made the unit stay on most of the time. Speakers can also be plugged into the splitter. That will be plugged directly into the Lightning FX units RCA mono input. Ambient sounds will no longer affect the control of the lights.
Hopefully this video is informative to first time yard haunters.