Abstract: An aerial vehicle may be outfitted with two or more digital cameras that are mounted to a track, a rail or another system for accommodating relative motion between the cameras. A baseline distance between the cameras may be established by repositioning one or more of the cameras. Images captured by the cameras may be processed to recognize one or more objects therein, and to determine ranges to such objects by stereo triangulation techniques. The baseline distances may be varied by moving one or more of the cameras, and ranges to objects may be determined using images captured by the cameras at each of the baseline distances.