The disclosure provides for a system of markers and methods of using the system of markers to provide a precise scene scale reference for captured aerial images. Each of the markers may include one or more pairs of aligned collimated light emitters, where each pair of light emitters is configured to emit two light beams that converge at a known distance from the marker. When two or more markers are used, the system of markers may be aligned in a unique physical orientation to form a shape of known dimensions (e.g., a line, a triangle, or square) that provides an accurate scene scale reference for captured images.