Atlas of Mars, Phoenicis Lacus quadrangle, MC-17

This mosaic is made with computer enhanced Mariner 9 pictures, rectified and scaled to a Mercator projection. Computer processing was performed by the Image Processing Laboratory (IPL) of the Jet Propulsion Laboratory (JPL). Processing included contrast enhancement and high-pass filtering which accentuates topographic features while subduing albedo variations. Photographic reproductions of the images were generated from the IPL digital magnetic tapes and mosaicked by the U.S. Geological Survey.

Horizontal controls were derived from spacecraft tracking data, which are based on astronomical definitions of the spin axis and system of longitudes in use during the Mariner 9 mission. The projection is based on a theoretical dynamical ellipticity of 1/192. The scale is based on an equatorial radius of 3393.4 km. Standard deviation in image placement is less than 5 km at map scale.