This study focuses on the determination of optimal photographing angle and overlapping ratio for automatic image stitching system using a non-metric camera module with motorized head. Photographing overlap was calculated considering the angle of view on different kinds of lenses and moving angle of motorized head per each option, and optimal photographing angle and overlapping ratio could be determined through the experimental result using the operating time, data volume and performance of image stitching. Through this experiment, we could find that it was effective to take a picture with $36^{circ}$ of interval(33.82% of overlap) in vertical direction and $24^{circ}$ or $30^{circ}$ of interval(36.51% or 20.63% of overlap) in horizontal direction using 35mm lens for automatic image stitching system.