Wednesday, May 09, 2007

New View

View New Orleans in three dimensions! A new map on loan from the Coastal Studies Institute at LSU features the Crescent City in a way you've never seen it before - stop by Hill Memorial Library in the next few weeks to view this addition to our exhibition, An Unnatural Metropolis. The exhibition will remain on display through June 2, 2007.

The 3-D image of New Orleans is termed an Analyph, which is a composite picture consisting of two slightly different perspectives of the same subject in contrasting colors that are superimposed on each other, producing a three-dimensional effect when viewed through two correspondingly colored filters. The 3-D relief observed in the image viewed through the appropriate glasses reveals the "bowl" shape of New Orleans. The relief in the image is greatly exaggerated to obtain the effect. The elevation data used to create the relief was derived from airborne Lidar (LIght Detection and Ranging), which is a highly accurate remote sensing technology that measures distances using lasers. The relief was overlaid with a 30-meter resolution Landsat Thematic Mapper satellite image obtained in 2005 after Katrina landfall. The colors in the image are created primarily from infrared light.

Special thanks to DeWitt Braud, Coastal Studies Institute, LSU, for facilitating the loan and providing interpretive text.