Penelope's first data

Pulau Weh - The images to the left and below were taken of the coral reefs with Penelope's hull mounted sidescan sonar. The frequencies are 50, 80, 200 and 455 KHz. A higher frequency gives better resolution but less range. Penelope can image the bottom to about 50 meters. The black band is the 'dead zone' directly underneath the boat. The images are fully geo-referenced, the basic idea is to piece together a high resolution map of the corals around the Pulau Aceh and Pulau Weh islands.

In addition to the sidescan, Penelope has forward looking sonar (to help me from running into any reefs) and two underwater cameras connected to a PC with GPS inputs; helps us keep track of exactly where the images were taken.