Comparison of results obtained by photogrammetry tools versus LED handheld scanning technique in architectural heritage. Application to plasterwork located in a world heritage site

Abstract

The Palace of Pedro I (1356–1366) of the Real Alcázar of Seville (RAS) is one of the best examples of Mudejar construction preserved in the Iberian Peninsula. The richness of the composition and materials used in the plasterwork that decorates the ceilings, walls, and arches, among others, is remarkable. In this work, three-dimensional model of plasterwork frieze located in the RAS was built to highlight its heritage interest, assess the state of conservation, promote its preservation, and disseminate geometries and reliefs of this decorative element. To obtain an accurate three-dimensional graphic documentation, two non-destructive techniques have been applied: photogrammetric SfM (Structure from Motion) and handheld scanner. Models obtained throughout two methods will reveal the suitability of both techniques in this kind of architectural decorations and the resolution and quality obtained by each one, analyzing their weaknesses and strengths.