Here we have New York City. Red dots are locations of Flickr pictures. Blue dots are locations of Twitter tweets. White dots are locations that have been posted to both.
"There’s not a whole lot of technology behind it," Fischer writes. “It’s a C program that runs through the photos/tweets in chronological order, plotting the earliest ones the most brightly and stepping the brightness down for points that don’t show up for the first time until later on. Points are also allowed to diffuse by a few pixels when there is an additional record for a point that is already plotted, with the brightness falling off exponentially as the point that is actually plotted gets further from its intended location. Each pixel is the somewhat weird area of 2.25 square miles because a smaller area made the whole-world image too big for Flickr to let me post it.”
Visit his Flickr set and you’ll find Tokyo, Los Angeles, London, Santiago, Amsterdam and Moscow among a host of other cities. The topography they create is mesmerizing.