Mapped by Stewart Long
Cartographer: Stewart Long
Published by gonzoearth
Ground resolution: 2.38 cm/px
Capture date: 2011-06-18T00:00:00
Publication date: 2011-07-09T00:00:00
License: Public Domain
On June 18th I spoke about neogeography and held a balloon mapping group demonstration with the California Map Society during the group's summer 2011 meeting in Vallejo, CA.
Some notes about the site and situation from CMS Northern California Vice President, Fred DeJarlais: "The site of our Northern California summer meeting this year is Vallejo, a city that was twice the state capitol – first for only 11 days, and a year later, in 1853, for a month. Named after General Mariano Guadalupe Vallejo, this San Francisco Bay Area city has now nearly 120,000 residents. One of California’s oldest cities, Vallejo is home to the Mare Island Naval Shipyard, now decommissioned, and is sprinkled with handsome Victorian and Craftsman-style homes and spectacular views of the Bay and the San Francisco skyline."
This flight was more of a group demonstration than an organized mapping effort. We did not have time to move around the area with the balloon, but the weather was nice and we were able to stand out in the middle of Capitol street as traffic was quiet. Filling a Southern Balloon Works balloon with helium. related note on this particular camera house: http://publiclaboratory.org/notes/gonzoearth/7-5-2011/yet-another-soda-bottle-camera-house In this picture the camera is shooting in continuous drive mode with a large SD card and a rubber band holding the shutter button down.
Because all of the image acquisition originated from the same general horizontal position there is a lot of distortion present in this map. The distortion is minimized over Capitol Street while increasingly exaggerated away from that area and with vertical objects in the scene. While it is not preferential to map in this way, we were still able to produce an updated map for the neighborhood from the short flight. As I brought the imagery together for this particular map I allowed some small errors and artifacts to exist because it would have otherwise not been possible to use all of the available images and make a map with a larger extent of the neighborhood. -Stewart Here is the end of the flight. we reeled in the balloon by hand as it was only around 700-800 feet of line. This particular spool can also adapt to a drill gun for a powered and faster reel in.
A video time lapse of some of the image processing. It is possible to combine oblique and vertical aerial data in this manner, using the ground level as a common denominator and allowing for apparent distortion in some vertical objects.
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