Photogrammetric Survey of the Historical Church of Nossa Senhora do Rosário and São Benedito in Brazil

In the history of cities and society, architecture plays an important role in the materialization of buildings, in the ways of life and in the constitution of an era. Documenting architectural heritage is an essential task for the conservation, management and collection of knowledge, however it is a time consuming and costly task. Presently, the application of digital aerial and terrestrial photogrammetry has made this process simpler, more agile and of relatively low cost. In this context, the objective of this study was to analyze the visual and geometric quality of the 3D model, of architectural heritage, generated by photogrammetric techniques. To this end, topographic mapping (reference) and aerial and terrestrial photogrammetric surveys of the Church of Nossa Senhora do Rosário and São Benedito, in Estrela do Sul/MG, Brazil, which is a historical and cultural heritage of the country, were carried out. Adopted as a reference, the 3D topographic model was generated by the points collected with a total station. To generate the photogrammetric 3D model, aerial photos were obtained using a UAV (Unmanned Aerial Vehicle) and terrestrial photos, acquired at strategic points. In both cases the PowerShot SX260HS camera was used. The two georeferenced 3D models were analyzed visually, considering texture and completeness, and compared geometrically through coordinates of homologous points. Comparatively, the photogrammetric 3D model presented results with a wealth of details far superior to the topographic ones and a geometry with centimetric discrepancies, showing that the method is suitable for generating 3D models relating to architectural heritage.