摄影测量中的前方交会与后方交会。前方交会时通过一对相片的同名象点来球物方坐标，后方交会是通过四个物方坐标来求六个内方位元素-Photogrammetry in the front of the intersection and resection. Forward intersection, through a pair of photographs of the same name as the point of the ball in object coordinates, and the