1. A computing system, comprising: a depth camera configured to capture depth information for targets in a field of view of the depth camera; an aiming assembly configured to dynamically and repeatedly change the field of view of the depth camera by physically changing one or both of a pitch and a yaw of the depth camera to change an aiming vector of the depth camera while the depth camera images a scene; a logic subsystem in operative communication with the depth camera and the aiming assembly; and a data-holding subsystem holding instructions executable by the logic subsystem to: receive from the depth camera one or more observed depth images including a plurality of pixels, each such pixel including a depth value indicating a distance to a surface in the scene imaged by that pixel; instruct the aiming assembly to automatically change the field of view of the depth camera by physically changing one or both of the pitch and the yaw of the depth camera while the depth camera images the scene so that the aiming vector points with a first predetermined pitch to a predetermined default far focus if a target is within a far range; and instruct the aiming assembly to automatically change the field of view of the depth camera by physically changing one or both of the pitch and the yaw of the depth camera while the depth camera images the scene so that the aiming vector points with a second predetermined pitch, different than the first predetermined pitch, to a predetermined default near focus, relatively closer to the depth camera than the predetermined default far focus, if the target is within a near range, relatively closer to the depth camera than the far range.