I have found that the biggest “gotcha” when working with a visualizer comes not from the differences with the plot versus reality, but rather with the fixtures. Every visualizer has its own library of lighting fixtures similar to the libraries that exist in lighting consoles. However, the visualizer fixture libraries must contain much more data than just the DMX mapping, because they have to emulate the actual output. In some cases, this can result in incorrect information that can lead to programming errors. For instance, if the zoom operates differently in the real fixture than it does in the visualizer library, you will find that all your programming relating to zoom will be wrong. Every narrow zoom you saw in the visualizer would be full-wide zoom with the real fixtures.
—From “Feeding the Machines” by Brad Schiller, PLSN, Sept. 2013
