An automated system includes improved height sensing. In one aspect, a on-head camera performs the dual functions of fiducial imaging and height sensing using an auxiliary off-axis light source and triangulation. In another aspect, an on-head height sensor is positioned to measure height at a location that is not beneath any nozzles. The sensor provides height information at a plurality of locations over the board, and a height map of the board is created. In yet another aspect of the invention, the above features are combined to provide an on-head camera that images fiducials and measures height at a plurality of locations such that a height map is created.