Last Sunday I had the pleasure to participate in making an aerial map, a very detailed overhead image of Dolores Park taken from 200’ to 400’. The fine folks at Public Laboratories have published the result. A couple of direct links: a full page slippy map and aerial video. I also got a nice single shot of the new Dolores Park playground (full size).
This kind of mapping comes from Public Laboratory, a cool non-profit helping ordinary people make their own aerial maps. You don’t need a satellite or fancy cameras on a plane to make a “satellite map”. All you need is a kite or balloon, a cheap point and shoot camera, and a little software.
I particularly like how low tech the setup is. The lift comes from something as simple as a mylar balloon filled with helium (we used a car dealership ad balloon). No fancy cradle, just some rubber bands holding the camera to a plastic soda bottle with the soda cap as the clamp. And no special camera, just an ordinary consumer camera set to continuous drive with another rubber band holding down the button. Launch, fly for awhile, pick the best photos, then stitch them together into a map. (That last part takes some effort; you can do it by hand in Photoshop or use the MapKnitter web app).
The Dolores Park shoot was mostly for fun, a nice way to be outside on a sunny day and excite a bunch of kids. But Public Laboratories participates in more serious projects too, like documenting the Deepwater Horizon oil spill. A key thing about this kind of mapping is anyone can do it relatively cheaply and quickly. You can also fly other sensors, they’re doing a lot of work in environment monitoring,
Many thanks to Stewart Long and Bobby Sudekum for letting me tag along on the fun photo shoot.