The Pixelpainter is operated by three pushbuttons. One to play or repeat the current image (this button is located directly next to the handrail), and two to cycle up or down the imagecounter. A single seven segment display is showing the current image number, but while the LED-strip is blinking the display is turned off to not emit disturbing light in the long exposure photography.

A potentiomenter sets the brightness at booting up the system and between each shoot it controls the speed of showing the image at the LED-strip. So it is easy to controll brightness and speed.

The image processing code was found online. This code would play the image with the filename frame000.bmp from the SD card. Pressing the button again would play the frame001.bmp image. If it couldn’t counter up anymore the displaying of image 000 would start again. This seemed odd to me, because it isn’t really userfriendly, so I improved the concept with the display to see the current number of the image and two buttons to change the number. Furthermore the loading bar while initializing the SD-card was implemented.

The Pixelpainter can only read Bitmaps (.bmp) with a width of 170px (height is not determined) and 24bit colordepth. I used Photoshop to convert into this format.

The edited code can be found here: https://github.com/marricjudge/pixelpainter

Parts needed:

Adafruit Neopixel WS2812 LED RGB Stip with 170 LEDs

Arduino Uno

Adafruit Datalogging Shield (adafru.it/1141)

SD-Card

7-Segement Display

10kOhm Potentiometer

3x Push Button

1x On/Off Switch

4xAA Battery Holder and Clip

UBEC DC/DC Converter – 5V @ 3A output

1×270 Ohm, 3x 10 kOhm Resistor

1000µF Capacitor (to protect the very first LED in the row)

Sources:

https://learn.adafruit.com/neopixel-painter?view=all 04.08.17

http://www.instructables.com/id/Digital-Light-Wand-ENGFIN/ 04.08.17

http://mrossphoto.com/digital-light-wand/ 04.08.17

and the explanations on arduino.cc and many other forums.