1. A three-dimensional photographing system comprising: a camera for photographing the shape of an object from positions around an axis in directions different from one another and specifying angle data indicating the rotational angle of each of the directions relative to another; a means for rotating partial geometric models photographed by the camera about a provisional axis specified by provisional axis data indicating the three-dimensional position of the axis in accordance with the relative rotational angle; an extraction means for extracting a region of each of the partial geometric models overlapping another one of the models, a calculation means for calculating the degree of displacement of the entire set of partial geometric models; an alteration means for altering the provisional axis data; a repetition means for rotating the overlapping region about the provisional axis as shifted every time the provisional axis data is altered and causing the calculation means to calculate the degree of displacement, and; an output unit for outputting a set of the partial geometric models as rotated around the provisional axis when the degree of displacement is minimum.