LED Paint Brush

The LED Paint Brush is a tool for photographers used to create novel and compelling light painting photographs. This meter long device includes a Parallax Propeller microcontroller (similar to the Arduino) capable of controlling 30 individually addressable RGB LEDs. The LED Paint Brush has been used to display data, generate vivid geometric patterns, and to recreate classic paintings from artists like Vincent Van Gogh (see below). Before delving too deeply into what the LED Paint Brush is however, here’s a little overview of light painting.

microcontroller light painting

Light painting is a photographic technique where a long exposure photograph is taken of a moving light source, creating an image that captures the contrails of the light’s movement (see image above). Utilizing long exposure means that the camera’s aperture is opened for an extended period of time, giving the light source more time to traverse physical space, as well as saturate the camera’s photo sensor. By moving the light in a coordinated fashion, the painter can trace out shapes, symbols, and the like. A similar phenomenon can be observed on the 4th of July (Amurica!) when can see tracers in your vision after having a sparkler waved quickly back and forth in front of you.

american flag light painted

At Embedded Aesthetics, we think light painting is a wildly exciting field because it offers a vast opportunity for enjoyment and expression, as well as an avenue for Mechatronic application.  Thus, we decided it would be fun to create a special tool that could be used to make more intricate light paintings. By combining a microcontroller, an LED strip, and some custom software, the LED Paint Brush was born. At the start of this project, we had numerous technical goals, but only two main artistic goals. The first was to paint entire swaths or sections of light simultaneously, rather than utilizing the traditional single light source. Building on this, the second was to recreate existing works of visual art in light painting form. As an example, we wanted to be able to take classic physical paintings such as Starry Night and reproduce them as a light painting.

light painted starry night

To meet these artistic goals, we needed to develop some technical capabilities of the LED Paint Brush. Most notably, we needed to create software that could drive a strip of 30 LEDs in such a way that it made interesting and coherent patterns of light. Additionally, to make the LED Paint Brush a useful tool, we had to develop a user interface that made starting, stopping, and changing the light patterns convenient. Regarding the physical form, we wanted to create a robust, yet mobile tool that made light painting fun and easy. Finally, in order to be able to recreate existing images as light paintings, we needed to write software that takes an image file (jpeg, png, etc.) and parses it into a form that can be used by the LED strip and microcontroller.

arduino light painting

The final form factor of the LED Paint Brush is an all aluminum body that somewhat resembles the look and feel of a medieval broadsword. We chose aluminum because it provides a sturdy, yet lightweight encasement for the sensitive electronics. Unfortunately, with all of the hardware, battery, and electronics added, the LED Paint Brush weighed more than we would like. We feel the issue is the excess aluminum supporting the LED strip which comprises about ⅔ of the device’s length.

LED paint brush

The final user interface for the LED Paint Brush was a simple up/down/left/right button combination on the handle. To switch between different color patterns you can use the left and right buttons. To change between variations in sub-patterns or modify things like frame rate or hue, you can use the up and down buttons. We felt that this interface could be improved with more buttons, but for a first iteration it was pretty good.

custom light painting tool

To learn more, check out these links: