Projection Lasers: Beam Effects with a Projector and Haze

Laser shows look spectacular, but real lasers are expensive and – depending on where you perform – may require safety training, permits and careful audience scanning. Projection lasers in LayerMapper MApp give you a similar look with gear you probably already have: a video projector and a haze machine.

How it works

A projector throws light in a cone. Normally you only see that light where it hits a surface. Fill the air with haze and every bright part of the image becomes a visible ray travelling from the lens to the wall.

If the projected image is mostly black with a few thin, bright lines, those lines become beams in the air. Move the lines and the beams sweep across the room – exactly like a laser scanner, only made of video.

What you need

• A projector. The brighter the better – beams are much dimmer than a lit wall. Point it towards the audience space or across the room, not just at a wall.
• A hazer for a fine, even haze. Fog machines also work, but thick fog swallows the beams.
• A dark room. Any ambient light kills the effect.
• LayerMapper MApp on an iPhone, iPad or Android device.
• Optional, soon: an Android TV box with the LayerMapper receiver (coming to Google Play) to get the image to the projector without a cable.

Building the effect in MApp

1. Start with black. Projection lasers are about contrast: everything that isn’t a beam should be pure black.
2. Use slices for beams. Create thin slices and fill them with bright content – a solid colour, a gradient or a shader.
3. Record the motion. Move the slices live and MApp records the movement together with the live clip textures. Save the recording as a preset and reuse it in every show.
4. Add shaders. Line-based shaders – including ones you generate with LayerMapper AI Shaders – turn into fans, tunnels and sheets of light in haze.
5. Sync to the music with BPM sync or Ableton Link, and trigger presets with a MIDI controller.

Tips for brighter beams

• Project thin lines, not wide areas: the projector’s light is concentrated in fewer pixels, so each beam is brighter.
• Keep the haze even. Run the hazer a few minutes before the show and keep air movement low.
• Use saturated colours – pure red, green or blue beams read better than pastel tones.
• Point the beams towards the audience at a shallow angle, so people look along the beams rather than across them.

Safety

Projection lasers are video light, not laser radiation, which removes the main eye-safety concerns of real lasers. Still, don’t point a bright projector directly into people’s eyes at close range, follow the haze machine’s instructions and check venue rules about haze and smoke detectors.

Summary

With a projector, a hazer and LayerMapper MApp you can build beam shows that look like lasers – and drive them from a phone. See the projection lasers tutorial and examples in the showcase.