What each light does at an event, the fixtures you will meet, how colour and DMX work, how to cable and power a rig, and how to hang it safely. Written for beginners. Read it, work through the two tools, then pass the quiz.
Lighting is not decoration. It decides what the audience looks at, how they feel and whether the CEO's face is visible when he speaks. Before you touch a fixture, know the job each light is doing. Every light in a rig has one of four jobs.
The main light on a person's face. Bright, white, from the front and above at about 45°. If the speaker cannot be seen, nothing else matters.
Even colour across the stage or a wall. Sets the mood and the brand colour. Soft edges, no hard shapes.
From behind and above. Puts a bright rim on the head and shoulders so the person lifts off the background. Never points at the audience.
Beams, gobos, strobes, moving patterns. Energy for music and entertainment. Rarely used during speeches.
A beam of light is invisible in clean air. A haze machine puts a thin, even mist in the room so beams show up as solid shafts. A little haze makes a plain rig look twice the size. Too much hides faces and sets off smoke alarms. Ask the venue before you use it, and never run it near a smoke detector.
The PAR can is the workhorse of event lighting: a simple fixture that throws a round wash of colour. It is the first light you will rig. PAR stands for parabolic aluminised reflector: a bowl-shaped mirror behind the lamp that gathers the light into a beam.
The classic. A 1 kW lamp inside a heavy aluminium can. It gives a warm, bright light and needs a dimmer to control it, because the lamp has no brain of its own. Colour comes from a gel, a heat-proof plastic sheet in the front frame. It draws about 4.3 A each (1 000 W ÷ 230 V). The can is too hot to touch for 15 minutes after switch-off.
The lamp type sets the beam. The names are on the lamp or the lens:
| Code | Name | Beam (roughly) | Use |
|---|---|---|---|
| VNSP | Very narrow spot | about 6° | Tight, punchy beams for haze. Long throws. |
| NSP | Narrow spot | about 10° | Strong beam, small pool. |
| MFL | Medium flood | about 24° | General purpose. The one you see most. |
| WFL | Wide flood | about 50° | Wide wash from a short distance. |
The modern replacement. A bank of LEDs behind a lens. Typical draw is 100 to 200 W. No dimmer pack, no gels, no heat to speak of. The LEDs mix their own colour and you set it over DMX. Common types:
In the B&W kit: LED PAR cans, moving heads and uplighters. Standard event lighting is LED PARs with moving heads on top.
A moving head is a fixture on a motorised base. It pans (turns), tilts (nods), changes colour, shape and focus, all on command from the desk. One does the work of ten static lights. It is also the most expensive and delicate thing on the rig.
Tight, sharp beam with gobos and a prism. Good for logos on a wall and patterns on the floor.
Soft, wide, smooth colour. No gobos. A wash head replaces ten PARs.
A very narrow, intense pencil beam. Made to be seen in haze. Dramatic from far away, useless for lighting a face.
Beam, spot and sometimes wash in one body. Flexible, but heavier and dearer.
Every function on a head needs a DMX channel: pan, tilt, dimmer, colour, gobo, zoom and so on. A typical head uses 16 to 24 channels. Many have a reduced-channel mode. You choose the mode in the fixture menu (next lessons). A fixture set to the wrong mode behaves wrongly, even if the address is right.
Set the DMX address on the fixture's display or dip switches. When the head is powered, it homes: it runs a self-test, spinning to the end stops and back. Wait for it to finish before you send it anything. A head that never finishes homing has a fault. Note it and swap it.
In the B&W kit: moving heads are part of the standard event lighting package, run alongside the LED PAR cans.
A PAR and a moving head cover most jobs. These are the rest. Know them by sight so you can pick the right one and rig it safely.
A long strip of LEDs. Washes a wall, a backdrop or the front edge of a stage from the floor.
Use for: cyc wash, stage edge, under tables.
A bank of bright warm lamps. Hits the audience with a wall of light. Very bright.
Use for: big moments in a party. Never aimed at faces for long.
A very fast flash. See the epilepsy warning in lesson 10.
Use for: short, announced effects only.
A soft-edged theatre light with a lens you can focus wider or narrower. Soft, flattering and quiet.
Use for: stage washes, speaker key light.
A hard-edged spot with shutters. You can shape the beam to a doorway or a lectern and project a gobo.
Use for: a clean key light on a lectern, logos.
A big manual spot with an operator. The operator keeps the beam on a performer or speaker as they move.
Use for: awards, concerts, big presenters.
A small LED fixture on the floor, pointed up a wall or column. Often battery powered with wireless DMX.
Use for: room colour in brand colours.
A string of lamp holders, like party lights. Warm and informal.
Use for: marquees, gardens, weddings.
In the B&W kit: LED PAR cans, moving heads and uplighters. Other fixtures are hired in when a job needs them.
You will be asked for "our brand blue" and "a warmer white". Know why LEDs mix as they do and why one white is not the same as another.
An LED fixture has red, green and blue emitters. Red and green make yellow. Red and blue make magenta. Green and blue make cyan. All three make white. It is the opposite of paint: more colour means more light, not less.
A fixture made from only RGB gives a slightly cold, greenish white. RGBW adds a real white LED, so whites and pastels look clean and skin looks natural. That is why the white channel matters on a key light.
White light comes in warm and cool versions, measured in kelvin. Tungsten lamps are about 3 200 K (warm, orange-white). Daylight is about 5 600 K (cool, blue-white). Mix them in one scene and one looks dirty. Pick one and stay with it.
Tungsten lights get colour from gels. Two correction gels matter. CTO (colour temperature orange) warms a daylight source down to tungsten. CTB (colour temperature blue) cools a tungsten source up to daylight. Use them to match a light to another.
DMX is the language that lighting desks speak to fixtures. Every light you control from a desk uses it. If you understand addresses, you can fix most lighting problems in two minutes.
DMX512 carries up to 512 channels on one cable. That set of 512 is called a universe. Each channel holds a number from 0 to 255: 0 is off or minimum, 255 is full. The desk sends the whole universe about 44 times a second. A fixture listens only to its own slots and ignores the rest.
A fixture's mode is how many channels it uses. A simple LED PAR might have a 4-channel mode (R, G, B, W) and a 7-channel mode (dimmer, R, G, B, W, strobe, macro). A moving head might have 16 or 24. Read the channel list in the manual, then set the same mode on the fixture and in the desk.
The start address is the first slot the fixture listens to. It uses that slot plus the next ones, up to its channel count. The next fixture must start where the first one stops, or its slots overlap.
A universe holds 512 slots and a fixture is never split across two. Twenty-four 24-channel heads need 576 channels, so they need two universes. Each universe needs its own output from the desk or node and its own cable run. Fixtures on different universes can share the same start address, because they are on different lines.
Start addresses: 1, 8, 15, 22, 29, 36, 43, 50
| Channels per fixture | Max fixtures in one universe | Start addresses |
|---|---|---|
| 4 | 128 | 1, 5, 9, 13, 17, 21, 25, 29 |
| 7 | 73 | 1, 8, 15, 22, 29, 36, 43, 50 |
| 12 | 42 | 1, 13, 25, 37, 49, 61, 73, 85 |
| 16 | 32 | 1, 17, 33, 49, 65, 81, 97, 113 |
| 24 | 21 | 1, 25, 49, 73, 97, 121, 145, 169 |
A DMX line also stops at 32 devices, whatever the channel count. Use a splitter after that.
DMX is a fast, low-voltage data signal, and it hates bad cable. Most "the lights are doing odd things" calls are cable calls.
The standard is the 5-pin XLR. Many fixtures use 3-pin XLR, which looks like a mic connector. Pin 1 is the screen, pin 2 is data −, pin 3 is data +. Pins 4 and 5 are unused. Use proper DMX cable, which has a 120 Ω impedance. Use a 3-pin to 5-pin adaptor when you must mix.
DMX goes from the desk in one line: out of the desk into fixture 1, out of fixture 1 into fixture 2, and so on. No T-pieces or Y-splits. The order on the cable does not have to match the address order, but each fixture must be in the chain. The last fixture needs a terminator.
A terminator is an XLR plug with a 120 Ω resistor built in across pins 2 and 3. Plug it into the DMX out socket of the last fixture. It stops the signal bouncing back up the line. Many rigs run without one and work fine. Add it when you get glitches. It is the first thing to try.
Wireless DMX sends the signal over radio to receivers on the fixtures. It is perfect for uplighters on the far side of a room, but it is only as good as the radio environment. Keep the transmitter in line of sight. Art-Net and sACN carry many universes over a network cable (Ethernet). This is the next step for big rigs: one cable, dozens of universes. For now, learn the cable and the address.
A lighting rig has three kinds of cable running over the same truss. Mixing them up is the commonest way to get hurt or to ruin a show.
Power cables put noise onto DMX cables that lie alongside them. Keep them on opposite sides of the truss, taped or clipped every metre, and cross at right angles when you must cross.
Many LED fixtures have a power-in and a power-out so you can chain them from one plug. The chain has a limit. Read the number printed on the fixture or in its manual, usually 4 to 8 LED PARs on a 16 A line. Tungsten is much heavier: about one PAR 64 per 10 A dimmer channel. Never chain past the stated number.
Watts ÷ 230 = amps. A 150 W LED PAR draws 0.65 A. Add every fixture on the circuit. Then stay under 80% of the breaker, because breakers trip on a steady load near their limit and lamps and motors draw extra when they switch on.
| Fixture | Watts | Amps | Max on 16 A (80%) | Max on 32 A (80%) |
|---|---|---|---|---|
| LED PAR | 150 | 0.65 | 19 | 39 |
| Moving head | 350 | 1.5 | 8 | 16 |
| Tungsten PAR 64 | 1000 | 4.3 | 2 | 5 |
| LED bar | 100 | 0.43 | 29 | 58 |
80% of 16 A is 12.8 A (2 944 W). 80% of 32 A is 25.6 A (5 888 W).
Dimmers and switching power supplies put electrical noise into the mains. That noise comes out of the PA as a buzz. Run lighting and sound from separate circuits, and where you can, from different phases of the distro. This is basic good practice and it costs nothing.
In the B&W kit: the 32 kVA three-phase generator feeds 63 A distros with four 32 A outputs each. Put lighting on its own 32 A output and sound on another, ideally on a different phase.
Every lighting desk is different on the surface and the same underneath. Learn the ideas and any desk will make sense inside an hour.
Telling the desk which fixture is at which address, in which mode. If it does not match the fixture, nothing works.
A list of fixture profiles in the desk, one per make, model and mode. Pick the exact mode.
A group is a set of fixtures you select together. A palette is a stored colour, position or beam you can recall onto any group.
Cue: a stored look, played on command. Chase: a loop of looks. Busk: playing it live, by hand, to the music.
The master scales a whole playback. The grand master scales every output on the desk. Blackout kills all light.
A button that turns a light on while you hold it and off when you let go. Good for hits, and for testing one fixture.
You can practise with no gear. Free desk software runs on a laptop and has a 3D visualiser: grandMA3 onPC, ETCnomad and ChamSys MagicQ PC. Download one, patch some fixtures, build a few looks.
A fixture weighs from 2 kg to 30 kg. If it falls, it kills. Rigging is not a place for improvising. Follow the rules every time.
Every piece of truss, clamp, shackle and stand has a safe working load (SWL) printed or stamped on it. Add up the weight of everything on it and never exceed the SWL. If it has no SWL, it does not go up.
Truss on stands (ground-supported, low) is a crew job when you have been shown how. Flown truss (hung from motors or the roof) is for certified riggers only. If you are not one, you do not touch it.
Tape or clip all cable runs. Never leave cable across a walkway without a cover. Outdoors, fixtures must be rated for it (look for an IP65 or IP rating on the label). Keep power connections off the ground and under cover. If it starts raining and the fixtures are not rated, switch off at the distro and cover them.
| Symptom | Check | Fix |
|---|---|---|
| Fixture dead | Power lead, power link limit, breaker | Swap the lead. Plug straight into a known good point. |
| Flickering | Power supply, loose plug, overloaded link | Reseat plugs. Split the chain into two feeds. |
| Wrong colour | Mode, address, white balance on the desk | Match the mode to the patch. Re-check the address. |
| DMX "spazzing" | Cable type, damaged cable, no terminator, too many fixtures | Swap the last cable. Add a terminator. Use a splitter. |
| Moving head not responding | Homing, address, mode, DMX in/out the right way round | Power-cycle. Wait for homing. Check the DMX in socket. |
Ten questions. Pick an answer for each, then press Mark my answers. You need 8 out of 10 to pass this module. You can retry as often as you like.
Ten questions. Circle one answer for each. The answer key is on the last page. Pass mark: 8 out of 10.