Abstract: A pair of photographs of the same object taken from different positions and fixed to a single carrying plate the position of which can be adjusted in a first plane. Three measuring devices are associated with the carrying plate for determining the coordinates of the plate to indicate the distance and angle of the plate relative to a fixed reference system. Binocular optical means includes two measuring marks respectively having lines of sight intersecting said two photographs. The lines of sight are parallel to one another and lie in a plane disposed perpendicular to the first plane. One of the marks can be moved relative to the other so that the lines of sight may intersect identical points on the two photographs. A fourth measuring device is provided for measuring the distance between said lines of sight. The outputs from the four measuring devices are fed into a computer for deriving three dimensional quantitative information about the object.