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Common pitfalls

My moving head fixture is powered and it moves as expected, but I don't see any light​

Advanced fixtures that work with a traditional incandescent bulb, as opposed to LED, require a special command sequence in order to turn on the bulb. Without this, the fixture will appear to be working but it will not actually light up. This is called the Lamp On command, and consists of a special sequence of dmx values on specific channels. This sequence is different for every fixture type.

Beam does not send these commands, so you need to power on the lamps manually on the fixture, or by specifying these commands in a macro on the nodes you use.

After receiving the Lamp On command, it can take some time, sometimes up to minutes, before a lamp is fully on and warmed up.

LED color changes seem choppy but the output frame rate is high​

We had an occasion where a DMX node with a fixed output frequency of 44 Hz (the maximum allowed output rate for DMX) caused a situation when controlling cheap LED tubes. The tubes, it turned out, would only work properly with 30 Hz.

Node with more than 4 ports: only first 4 ports are working​

Some nodes have more than 4 output ports. Standard Art-Net can only carry 4 universes per IP address. That is why 8-port nodes typically receive on two IP addresses.

Node with more than 4 ports doesn't have two IP addresses​

In some cases, a node can also be used as a DMX extender, intending to use two of them, one for input, one for output. To facilitate that, they develop their own extended Art-Net-like protocol that supports more than 4 universes per IP address. This will unfortunately not be helpful when converting standard Art-Net to DMX, so when using this node in its standard mode, as an Art-Net to DMX converter, only the first 4 ports can be used.

Node doesn't receive Art-Net signal from Beam when in broadcast mode​

Some nodes have the limitation that they don't process packets sent by broadcast but only by unicast. In this case, Beam needs to be set to unicast mode. Since Beam can currently only output to one IP address in unicast mode, this means that a maximum of 4 universes can be output, even with more nodes or if a single node has more than 4 ports.

My fixture doesn't behave like it says in the manual​

Fixtures come with firmware. Sometimes, with different firmware than expected, fixtures will behave slightly differently than stated in the manual, resulting in very different visual results. Manuals should always specify the firmware that a DMX chart is based on and you should always be able to find out what firmware version is installed on the fixture, usually by looking at its LED screen when booting up.