Perspective center determination

This program determines coordinates of the perspective center of a stereoplotter projector by bringing two bundles of rays into a best fit coincidence in a space-resection solution. One of the bundles of rays is defined by the perspective center and the grid intersections on a grid plate. The other bundle of rays is defined by the perspective center and the projected grid intersections in the model space. The program is used with the independent-model method of semianalytlcal aerotriangulation, which requires the coordinates of perspective centers. It may also be used in checking the calibration of stereoplotters.