Surveying for documentation and management of the Renaissance building Royal Hospital in Granada (Spain)

Surveying an historical building for documentation and management is a complex task because usually it concerns more than a unique technique. We have surveyed and modeled the Royal Hospital from Granada, Spain (1511-1526). In our case, the main tool for data capture was a Laser-Scanner. Nevertheless, unavoidable shadows appeared in every Scanner station, and some of them had to be covered by photogrammetry in order to avoid holes in the subsequent modeling task. Photogrammetry was also used in order to increase the points cloud in some areas where more detailed surfaces were needed, e.g. entrance front, arms, impaired columns... The accuracy, achieved in areas where photogrammetry was applied, was similar to the Laser-based one. Two precise traverses were necessary in order to get a precise alignment from the different Scanner stations, if we hadn't use two traverses it would be impossible to get a precise alignment because the existence of inner Scanner stations. In the modeling and texture stages, special attention had to be paid to the dome, arcs, columns and wood frames because details and corners needed additional edition processing.