Last week we very briefly went through the history of lighting technology and this week’s topic is on lighting design. But before we dig in to lighting design I want to show you basic lighting equipment and why we use them in lighting design.
In the previous article we talked about the ERS spotlight (Or in our case ETC Source 4s) that uses two plano-convex lenses to focus the lighting onto the stage. In theatre that is the main way that we do lighting. We use over 100 ERS spotlights that are pointing in different directions and we use the lenses to blend them together. We also use PAR cans as a flood light to generally light an area. Those types of fixtures don’t have two lenses and generally have a soft edge. They also don’t have any shutters, unlike the ERS spotlight, which block the light from going into places we don’t want like an audience area. There are many uses for the PAR can light but it is typically used as top lighting because of how it spreads light.
The dimmer rack allows for the control of all of the incandescent lighting fixtures. Each fixture plugs into a circuit that can be individually controlled. The dimmers change the voltage waveform which allows the light to be bright or at a low intensity. Each circuit is capable of 256 levels of intensity from zero being off to 255 being completely on. The dimmers are connected to the lighting network to allow them to be controlled by a lighting console. Non-incandescent fixtures like LEDs are not plugged into the circuits. LEDs need a constant voltage in order to run but they can be plugged into a circuit if the circuit has a relay which keeps the voltage at a constant level just like if you plugged it into a standard socket. That is often called parking the circuit since you are keeping it at a specific level. Lights like LEDs, once powered, are then controlled via DMX and connect to the lighting network.
A lighting console is then used to run the dimmers and other DMX capable devices. At the University of Wisconsin-Milwaukee the board used in the MainStage theater is the ETC ION. On the light board you can control lights individually, as groups or even apply effects to them like a strobe. LED fixtures can be set to specific colors using a color picker or if you have a color in mind the RGB values. A lighting console is really when a show comes to life and playing with levels, fades and effects can really add to a performance. A lighting console can also just be a normal computer with software that allows control of the network. ETC makes a virtual console called ETCnomad which is in the EOS family of software just like the ION. The software is free from ETC but requires a special device to output the DMX/E1.31 signal into the network. There are also free lighting console programs like sACN View and OLA that allow for control of the network over E1.31 with ethernet and several other protocols. But unlike the nomad software they are very much limited unless you know how to code your own interface.
Each theater has their own equipment and a way of connecting it all together. We are lucky to have a very powerful lighting network here at UWM that allows everything to get connected very easily and efficiently!
In our next article we will go over the basics of lighting design! Thanks for reading!