Oprah likes to tell people that they need to set limits and boundaries with others so that relationships work within certain parameters. Much in the same manner, you can set limits on parameters within the patch functions of most consoles. By limiting a parameter, you can adjust its true maximum or minimum value. For instance, if you have four 500W fixtures and two 750W fixtures, you may want them to all appear the same onstage. You can limit the maximum intensity of the 750W fixtures to a level that is equal to the 500W fixtures’ full intensity. This way when you put the fixtures at full, the console will actually limit the output to 75 percent of the fixtures’ capability. In the console data it will still read as full, but the DMX data will be limited accordingly. This can also be useful with position information, as you can limit the pan or tilt range of a fixture. By doing so, you can ensure that a fixture never projects to a certain location onstage. Limits on other parameters such as media server folders, zoom settings or gobo wheels can prove handy in many situations.
—Brad Schiller, from “Feeding the Machines,” PLSN, Nov. 2011
