Title: LOW COST DIGITAL PHOTOGRAMMETRIC TECHNIQUES FOR 3D MODELIZATION IN RESTORATION WORKS. A CASE STUDY: St. DOMINGO DE SILOS’ CHURCH (XIVth CENTURY, ALCALA LA REAL, SPAIN). Author: M. Ramos, J. Cardenal, E. Mata, M.A. Hernandez, J. Delgado, J.L.Perez, M. Torres, P. Castro Presenting Author: E. Mata Institution: E.P.S. University of Jaen. Spain WorkingGroup: I-II Keywords: 3D, Digital Camera, Digital Photogrammetry, Model, Restoration Presentation: Poster Abstract: LOW COST DIGITAL PHOTOGRAMMETRIC TECHNIQUES FOR 3D MODELIZATION IN RESTORATION WORKS. A CASE STUDY: St. DOMINGO DE SILOS’ CHURCH (XIVth CENTURY, ALCALA LA REAL, SPAIN). J. Cardenal, E. Mata, M. Ramos, J. Delgado, M.A. Hernandez, J.L. Perez, P. Castro, M. Torres This work is about a complete photogrammetric record and the 3D modelization of St. Domingo de Silos’ Church (XIVth century), in Alcala la Real (Jaen, Spain). The church is located in the impressive fortress of La Mota Castle that it was a strategic stronghold during medieval times. The fortress (declared National Monument in 1931) was the scene of frequent battles between the Moors and the Christians. The origin of this church dates from the XIVth to XVIth centuries. It was the first church founded in the city of Alcala, above the rests of an old mosque. The church is gothic mudejar style, but large reconstruction was done at the end of XVIth century. At present it is a ruin heavily damaged and near to collapse, so local authorities decided urgent actions for the reconstruction. Previous to the restoration works, different surveying and photogrammetric techniques were used for a reconstruction project of this important historical building, but at moderate costs with the extensive use of non metric and semi-metric instrumentation. To maintain low costs, the main final products, in case of planar surfaces, were mosaics of rectified photographs, although orthophotographs, cross sections, stereoplotting and structural analysis of deformation of walls and a vault were also made in order to support the final architectural restoration project. Finally, after the photogrammetric recording, a 3D modelization with all available data was carried out. This was an accurate photo-realistic model with real textures taken from the image mosaics (made from the rectified images and the orthophotographs). The process to create the geometry of facades, walls, arcs, vault, etc. and their integration in the same model with textures was mainly done under CAD (Autocad) and 3D modelling (•3D Studio) programs. Also photo-realistic walkthrough movies and anaglyphic images (extracted from the model) were done in order to show in a future the present ruin state of the church. The paper analyse in brief the full photogrammetric project, the evaluation of the non metric instrumentation and methods (both data acquisition-reduction) used, the creation process of the model and also the evaluation of additional widely used 3D modelling software for more detailed parts in the general model.