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Public Lab Research note

Lima, Peru (Infrared)

by warren | June 06, 2011 15:43 06 Jun 15:43 | #335 | #335

Mapped by Jeffrey Warren, Roxana Garrido, Morflex, Diego Rotalde, FabLabLima

Cartographer: Jeffrey Warren

Published by warren

-12.136478977990128 N, -76.97399975585003 E


Capture date: 2011-01-18T00:00:00

Publication date: 2011-01-26T00:00:00

License: Public Domain


We flew at the athletic fields of Ricardo Palma University, on east side of Lima, and after a turbulent flight, the string broke, and the camera flew off, leaving us depressed and exhausted.

We had built a large airfoil-shaped balloon from three sleeping bags tied together with a 2 meter wide, 1/2 inch thick PVC tube which we found near the field. It generated so much lift in the light winds that it broke right through the 50-pound dacron kite string and flew away.

"Glometa" ready to fly

Luckily we'd put Beno's name and phone number on the camera rig, and he got a call that night; a friend picked up the camera 15 miles south of the launch site, and it was full of imagery from around 2 miles up (estimate). Amazing!

This camera had a bifocal filter, half infrared pass, half visible light pass. You can read more about this infrared balloon technique here:

Our bifocal infrared/visible filter

Cartographer notes

This flight was unique because it was the first infrared/visible multispectral camera we'd attempted to fly on a high altitude flight. With the lucky break of recovering the camera even though the string broke, this dataset was amazing to work with -- I spent some hours making both an infrared and a visible stitched image, shown here:

infrared and visible balloon maps from Lima

An alternate version of this is viewable here, using a heat-map color gradient to represent the data using the NDVI, or Normalized Differential Vegetation Index technique:

Public Laboratory balloon NDVI of Lima in false color


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