English: Compound positioning trace of the underwater exploration at Cape Armitage with the SCINI ROV (Moss Landing Marine Lab), November 2009. The plot was obtained with the Desert Star PILOT Short Baseline (SBL) acoustic positioning system. Grid spacing is 50m, and coordinates are UTM. Baseline transducers were deployed at the three southernmost of the four locations marked by red dots, with a spacing of approximately 22m. The small color coded dots represent the ROV position fixes. The depth range is 23m (dark green dots) to 108m (red dots). Precision analysis: The record contains approx. 10400 position fixes, with a median slant range between surface transducer S1 and the ROV of 93m. The median precision with an applied position averaging period of ten seconds (equivalent to approx. three successive positions) is < 0.54m. This computation is based on the assumption that the entirety of each jump between two successive positions is due to the precision limit or jitter. In reality, a portion of it is due to the ROV motion along its path, thus making the 0.54m number a worst case assumption.