DIGITAL AND ANALYTICAL PHOTOGRAMMETRIC RECORDING APPLIED TO 
CULTURAL HERITAGE. A CASE STUDY: “St. DOMINGO DE SILOS’ CHURCH (XIV 
CENTURY, ALCALA LA REAL, SPAIN)" 
E. Mata* ', J. Cardenal", P. Castro", J. Delgado”, M. A. Hernandez", J.L. Perez’, M. Ramos, M. Torres“ 
Dept. Ingenieria Cartografica, Geodesica y Fotogrametria. Escuela Politecnica Superior. Universidad de Jaen. 23071- 
Jaen (Spain) — (emata, jcardena, pjcastro, jdelgado, acaro, jlperez, mtorres)@ujaen.es 
KEY WORDS: Architecture, Cultural Heritage, Reconstruction, Rectification, Close Range, Non-Metric, Digital 
- 
ABSTRACT: 
This paper is about a complete photogrammetric record of St. Domingo de Silos’ Church (XIV century), in Alcala la Real (Jaen, 
Spain) It was declared National Monument in 1931. At present it is a ruin heavily damaged and near to collapse. So, local 
authorities have decided urgent actions for the reconstruction. Previous to the restoration works, different surveying and 
photogrammetric techniques were used for a reconstruction project and cataloguing of an important historical building, but at 
moderate costs with the extensive use of non metric and semi-metric instrumentation. A wide variety of photogrammetric methods 
and instruments has been applied: analytical and digital plotters; terrestrial metric, semi-metric (reseau plate) and non metric cameras 
(analogical and digital). Stereoscopic pairs, when possible, were taken with the help of a device which allowed for stereoscopic 
shots. Convergent photographs were also taken in order to reach a favourable geometry for bundle adjustment (selfcalibration) and 
control point densification. Both photogrammetric and desktop scanners were used. To maintain low costs, the main final products, 
in case of planar surfaces, were mosaics of rectified photographs. Cross sections, modelling and structural analysis of deformation of 
walls and a vault were also made in order to support the final architectural restoration project. 
1. INTRODUCTION 
The St. Domingo de Silos’ Church is located in the impressive 
fortress of La Mota Castle in Alcala la Real (Jaen, Southern 
Spain, Figure 1). The place was a strategic stronghold during 
medieval times, and subsequently occupied by the Moors in 
713. Thereafter, Alcala was the scene of frequent battles 
between the Moors and the Christians. The origin of this church 
dates from the XIV" to XVI? centuries. It was the first church 
founded in the city of Alcala, above the rests of an old mosque, 
after the fortified city was conquered to the Muslim Kingdom 
of Granada in 1341. The church, built in XIV" century, is 
gothic mudejar style, but large reconstruction was done in the 
sacristy and tower at the end of XVI" century. It presents an 
asymmetrical ground plan with two large rectangular naves, the 
main chapel (with a strange plan, between trapezoidal and 
rectangular) covered by a rib vault, the sacristy and a square 
tower (Ayto. Alcala la Real, 2003; Figure 2). 
Because the historical importance of this church, it was 
declared National Monument in 1931. The original paintings, 
sculptures and furnishings of the church are now dispersed in 
private collections, in other churches in Alcala la Real and 
Granada cities or lost. At present it is a ruin heavily damaged 
and near to collapse after injuries during the Spanish War 
(1936-39) and further decades of abandonment. So, local 
authorities have decided urgent actions for the reconstruction. 
Previous to the restoration works, the monument has been 
     
CAR Sd = la 
documented by means of photogrammetric and surveying Figure 1. A: Panoramic view of La Mota Fortress, Santo 
techniques (UJA, 2003). Since the financial cost of the Domingo de Silos’ Church (white rectangle) and geographical 
Photogrammetric survey had to be kept low, extensive use of location of Alcala la Real (Jaen). B: Main facade, south side; C: 
non metric and semi-metric instrumentation and mosaics of General view from south-western side (belfry, nave, arches and 
digital rectified images were used. access to the chapel are visible),; D: Bell tower and north wall; 
E: Panoramic of east walls.