Digital light painting is a consummate maker project, a marriage of electronics, code, photography…and of course lots and lots of LEDs!

Using a long (several seconds) camera exposure, a single row of LEDs under computer control displays an image one line at a time while it's carried or rolled across the frame. The combined result is a luminous picture floating in air.

We’ve done light painting guides before — like our original Light Painting with Raspberry Pi and the Arduino-based NeoPixel Painter — it’s a topic we like to revisit whenever there’s a substantial evolution in the available technology. Each used a new generation of addressable LED strips.

This latest blend of Raspberry Pi computer and DotStar LEDs may be the ultimate, with no size constraints, easy image loading (just plug in a USB flash drive full of pictures) and super buttery smooth interpolation and dithering.

Required Parts

Raspberry Pi computer: the code runs fine on any Raspberry Pi, but we really recommend a recent model with the 40-pin GPIO header (not an original 26-pin Model A or B), because…
Perma-Proto Pi HAT: installs neatly atop the Pi’s 40-pin GPIO header, providing a sturdy connection point for various other parts.
2GB or larger microSD card.
USB flash drive for loading images.
DotStar LED strip: any length and density will work, but 144 LED/m is ideal. 1 meter is good for a painter that’s still easy to store and transport. I built a 2 meter painter, but that was mostly to showcase the added horsepower of the Raspberry Pi…it’s harder to build and unwieldy to move around! NeoPixel strip will not work for this project; must be DotStars for speed.
74AHCT125 level shifter IC.
Six (6) momentary pushbuttons.
Large USB battery bank or other 5V portable power source. The more current it can provide, the brighter the images can be. Or use two.
Two (2) USB Type A male DIY connectors if using a USB battery bank.
Soldering paraphernalia, wire, etc. A solderless breadboard and jumper wires may also be useful during initial testing.
An opaque enclosure for the Raspberry Pi (or get creative with tape, paint, etc.)
Hardware store bits & bobs.
A 3D printer is optional but may be handy for improvised brackets, cases and parts.

READ THROUGH THE ENTIRE GUIDE FIRST for more parts and construction ideas. Every painter will be a little different, depending on what materials and tools you have access to.