Tenebrae

What is Tenebrae?

Tenebrae designs shadow lamps made of two perforated shells, cylinders or spheres, nested around one LED. Light reaches the room only where both shells are open, so the two patterns combine into moiré lobes on the ceiling and walls, and turning the outer shell moves them. The preview traces the light through both shells into a room, with room, wall, ceiling and lamp views.

The sidebar works through eight steps: table lamp or pendant, where the pattern should land, the light (ideal point, LED die, filament or frosted bulb), the shells, the pattern (slots and spirals, rings and waves, phyllotaxis dots, Voronoi cells or a superformula lattice), the moiré detune, manual twist or a motor, and the process (FDM, SLS or laser-cut sheet). There are fourteen presets, a Randomize button with per-slider locks, and a Basic mode that shows the 23 main controls. Checks under the preview remove floating islands and count thin webs, tiny holes and FDM overhangs for each shell.

The 3D print export is a ZIP with one watertight STL per shell, half or cap, the design file, a checks report, and shell profiles with a Fusion script for designing a base in CAD; the laser-cut export gives SVG and DXF files. It is free with no account, and the code is MIT licensed, which covers the software, not prints. The tutorial suggests matte black PETG or ASA and names a specific LED, driver and stem, so finishing the lamp takes a small electronics build. It suits makers who want a lamp that draws on the ceiling and are happy to wire it up.

What you can make

• Two-shell shadow lamps
• Moiré ceiling and wall patterns
• Table uplights and pendants
• Laser-cut lamp shells as SVG or DXF

How to use Tenebrae

1. Load a preset such as the table uplight
2. Pick the target, the light and the shells
3. Tune the pattern and moiré, and read the checks
4. Export the STL ZIP or the laser-cut files