All around you are wireless data networks: cellular networks, Wi-Fi networks, a world of wireless communication. Check out this awesome video of network signals mapped over a cityscape.
What would happen if you made a device that allowed you to map signal strength onto film? In the following video electronics tinkerers craft an LED meter and use it to paint onto long exposure photographs with phenomenal results.
Video is here;
WiFi-Light-Painting
Reference;
Lightscythe Creates Hugh Light Paintings
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