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The lighting board is what the M.E. or L.D. uses to run the lights
for a production. Many different styles of boards exist, with
a wide range of capabilities and features. Portable lighting boards
are actually a fairly recent concept. Early systems
required the controls for dimming the instruments to be part of the
dimmers due to mechanical limitations. Within the past twenty years
or so, schemes for running the dimmers remotely have been developed,
some of which are discussed in detail in the next section. These
innovations have helped to bring about the creation of separate
The simplest lighting board one is likely to find today allows the
operator to set up two scenes and cross-fade between
them. These are commonly referred to as X-Y boards. An X-Y
board has a number of channels associated with it, where each channel
can control one or more dimmer channels. For example,
twelve channels may be controlled with a small board. Levels can be
set for each of these individual channels on two scenes (the X and Y
scenes). A cross-fader allows switching between scenes -- as one
scene comes up, the other goes down, and vice versa. One scene is
generally in use at a time. While the other scene is inactive, it can
be pre-set for the next scene, which is generally done from a
sheet of paper with the appropriate levels written on it.
Small but powerful lighting board, manufactured by Leprecon/CAE, Inc. This board is used to run the lights in many
of the small productions at WPI.
Most boards also allow some form of soft patching, meaning
assigning more than one individual dimmer channel to a board channel.
This is advantageous because each dimmer channel is rated for a maximum
power handling capability. Soft patching allows more instruments
to be controlled as a logical unit than a single dimmer channel allows.
Older lighting boards use a matrix of diode pins to electrically
connect board channels to dimmer channels. Modern boards tend to
accomplish the same task through the use of software.
Advanced lighting boards usually provide all of the same features as
an X-Y board, but add the ability to store scenes, record a sequence
of scenes in a cue stack, and record light chases.
Scene storage is an especially handy feature because it becomes
increasingly difficult to set an entire scene when the number of
channels on a board is high. With a standard X-Y board, every fader
in a scene has to be set to a level recorded on a piece of paper.
Scene storage boards remove this hassle by allowing the operator to
record a scene and assign it to a single fader. More advanced boards
allow these recorded scenes to be strung together into what is
commonly known as a cue stack. This enables the operator to simply
push a ``go'' button to advance to the next lighting cue. Lastly,
some boards allow repeating sequences of scenes to be run. Most are
outfitted with a speed control that allows the operator to adjust how
quickly the sequence progresses. Some boards even provide an input
for an audio synchronization signal, such that lighting chases may be
synchronized with an audio track. See figures 5.19 and
5.20 for examples of advanced lighting boards.
Large lighting board, manufactured by Leprecon/CAE, Inc.
It features 48 channels, 96 scene presets, cue stack, programmable chase,
and a floppy disk drive for storage and retrieval of board programs.
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