Considerações sobre o levantamento de áreas extensas pela fotogrametria aérea


  • Ferdinando Bianchi


Engineer Ferdinando Bianchi, an enthusiast of the aerophotogrammetric surveys, following a foreword by Major Adir Guimarães, writes about such a practise over extensive areas, as in the case of Brazil.

            He starts off with the methods used hitherto for land surveying and advocates aerial photogrammetry "which affords an ideal solution for a unparalleled swift, thorough and accurate work extremely valuable both for the rapid compiling of small-scale maps and the rigorous stereophotogrannnetric restitution o f large-scale maps.

            He delves into details of the aerophotogrammetric techniques and analyses minutely, in an increassingly order of accuracy, the following works. (I) compilation of a simple uncontrolled mosaic; (2) .compilation of a controlled mosaic; (3) aerial triangulation on planimetry; (4) .special aerial triangulation; and (5) complete stereophotogrammetric restitution of maps. -Of all of these, technical features, apparatuses that should be used, advantages and inconveniences are shown.

            He displays a permanent concern towards having his studies applied to the Brazilian case. Here the territory is vast and, considering the cost of operations, methods for accuracy in an initial work should vary according to the economic value of the region to be surveyed. He ends by presenting a project with an estimate of the expenditures for a survey in the State of Maranhão.