I've done light graffiti in the past and always find the results and process so much fun. I wanted to take it a step further and work on my maker skill to build a light graffiti skateboard. Here is how I did it.

Supplies

An old skateboard that you aren't afraid to drill holes in
4mm zip ties
Neopixel led strip
Arduino nano
3 pin led connector
2 pin power connectors
7.4 Lipo battery, the smaller the better
Camera capable of long exposures, you can use a smart phone on manual
Tripod
Flash - I used a softbox, but you can also use a bare flash off camera

Step 1: Prep the Board

I drilled holes every 6-9 inches along the board, this would be to hold the LED's in place with the zipties. I tried to keep them as close to the edge as possible.

Step 2: Assemble Arduino

I used an Arduino nano to power to project in order to keep the weight down. I 3D printed this case from thingverse. I connected a button and switch so I could turn it on and off, and cycle different light affects. In the end I only really used the rainbow effect. For simplicity sake I could have simply plugged the battery and removed the switch and button.

I used a single 7.4 lipo battery. You can see the basic arduino sketch, this is the simple version with no button or switch for power. Keep in mind the diagrams are using a Arduino Uno, but a nano is needed.

Step 3: Programming the Arduino

I decided to go with the fastLED Arduino library, but you can also use the NeoPixel library if you are more familiar with that.

There are two sketches attached one with the button that cycles several light effects and one with no button that uses the rainbow light pattern. Even though I had a had programmed several light patterns I used the rainbow pattern the most.

Here is an example on Tinkercad using the NeoPixel library:
https://www.tinkercad.com/things/7NkVtp6PWm0

Note: Tinkercad requires the Neopixels to take power from the from the Arduino, but in order to power a full 115 LED strip you'll need to draw from power from the battery.

Note: You'll need to change the LED count to match the amount of lights you have for your strand.

Step 4: Full Assembly

I secured everything to the board with short screws, glued down the battery with hot glue gun, and connected all the components for a test.

Step 5: Getting the Shoot

Put your camera on your tripod and set up your flash. Your camera will need to be on shutter priority. I triggered the flash manually with the flash "test" button when the subject was at the right spot.

Depending on the ambient light in your surroundings you'll have to change your ISO and f-stop. It is best to do this with a number of test shoots. In the end I used ISO 1600 and at f11 for most of my shoots. You set your shutter speed based on how long you want your light trails, I used 4 seconds.

It takes a lot of testing to get it all right!