Abstract: A photographic sensing module comprises a substantially rigid frame having legs diverging away from a camera mount; and an outer enclosure excludes the camera lens from exposure to external light while evenly diffusing the light from an internal light source mounted within the module, the legs serving as markers for the instrument. A portion of the frame defines the angle of view of the camera lens and diffuses the light evenly over the subject plane while excluding it from direct exposure to the camera lens. The subject plane is divided into generally rectangular grid segments of predetermined size, and a camera is spaced in relation to each segment such that the angle of view corresponds to the size of the grid segment. Special reference markers identify the periphery of each grid segment to be photographed, the camera is successively positioned to photograph each grid segment, and the images of the grid segments are reassembled into a photomosiac of the subject area.