A Hillshade is a shaded relief raster from a raster. Simply, when used with maps, it provides a three-dimensional aspect to the map based upon the relief of the underlying area. A more detailed definition of a hillshade can be found here.
This hillshade was computed from the 2006 Digital Elevation Model (DEM) acquired by the Los Angeles Regional Imagery Acquisition Consortium (LAR-IAC), and is a 5 foot by 5 foot raster grid. This hillshade has been improved by Hwa Saup Lee of the County’s Internal Services Department to smooth the differences between the two LAR-IAC collection areas (high resolution 5 foot and low resolution 10 foot) and create a single seamless hillshade.