Control Densification by Analytic Photogrammetry

Numerical methods in photogrammetry began to receive wide-spread attention in the early fifties with the development of the large digital computers. The Worldwide Satellite Triangulation Program of the sixties proved that, with care and deliberate production controls, first-order geodetic accuracies could be obtained for precision photogrammetric cameras and numerical data reduction. Research is presently underway at the National Ocean Survey to develop equipment, flight configuration, and reduction techniques that will provide internal photogrammetric pointing precision of at least one part in 250,000 of the flight altitude for conventional mapping. The projected goals of the system are to produce ground coordinates with a standard deviation in position of —2.5 cm over an area of 48 km with peripheral horizontal geodetic control spaced at 16 km.