DMX512 (digital multiplex) is the state-of-the-art standard for digital communication networks which is used in many professional settings such as concerts, stages and studio lighting. It allows lighting designers to work with more lights than ever before. A DMX Network consists of one DMX512 Controller (master) and one or more so called slave devices. Typically, a lighting console (DMX control desk) is used as a controller for the network and the slave devices can be dimmers, intelligent lights or fog machines. The DMX control desk has an OUT connector and is connected via a DMX cable to the IN connector of the first slave (e.g. light). A second cable links the OUT connector of the first slave to the IN connector of the second slave and so on. Together this is called a DMX universe and the chain of devices is called a daisy chain. In my second tutorial I will show you how to do this.
Below I describe the required control desks and how you address lights correctly.
Below I describe the required control desks and how you address lights correctly.
DMX Control Desks
DMX control desks are available in different sizes. The size of the desk limits the number of channels (ch) which can be controlled with one desk. The standard sizes are: 24ch, 48ch, 192ch and more than 192ch.
Depending on the lighting fixture, you need more or less channels to control the device. For example, a simple RGB fixture will requires only 3 DMX channels for the different colors, whereas a Moving Head requires at least six to control colors and movement. Most control desks all have some common featrues. Usually they have at least one fader which can be used to control the values between 0 (no light) and 255 (full light). This is also referred to as dimming. Also, they all have a "Black Out" function which turns off all the lights connected to the DMX daisy chain. The bigger desks with more than 192 channels offer a grouping called lighting fixture with 8-16 channels. So if you have bigger lights like a moving head you can easily control all its functions. This means though that if you have address the lights the first light would have the DMX address 1 while the second light would have the address 17. On the top image you see a 192ch board and on the bottom a 192 and more board. |
AddressingAddressing the lights correctly is the most important thing when using DMX controllers. Addressing a light will give the light a start DMX channel which means that is where the signal will be sent for that individual fixture. Each fixture will require a number of channels to work. Depending on the number of channels a fixture has, you will then address the rest of the fixtures on the next available channel.
For example, if we were to use a desk with 192 DMX channels with 12 fixtures, every fixture would get 16 channels. If the first light has address 1, the second light would have address 17 and so on (see table on the left). When using DMX you can also give two lights the same address. This would mean though that the lights which share the address will do exactly the same thing. To address a light there are two options. The first being DIP switches, which are commonly found on older/cheaper lights (see picture) or a digital menu. |