Considered the prototype of the Andalusian palace, Casa de Pilatos serves as the permanent residence of the Dukes of Medinaceli. The building is a mixture of Italian Renaissance and Spanish Mudéjar styles and is decorated with around 150 different azulejo designs of the 1530s made by the brothers Diego and Juan Pulido – one of the largest antique azulejo collections in the world.
This project is possible thanks to an ongoing collaboration between Factum Foundation and Fundación Casa Ducal de Medinaceli, which began with the 3D scanning of the marble sepulchre of Cardinal Tavera by Alonso Berruguete. The work in Casa de Pilatos, one of the most interesting and complex places we have worked on, involves the application of non-contact digital technologies to the documentation and study of key art and architecture elements in the building.
A range of digital technologies, including the Lucida 3D scanner, a FARO laser scanner, close-range photogrammetry, and composite photography were used to document the current state of the building, as well as to propose alternative approaches for its preservation and dissemination. Students recorded the walls of the Casa de Pilatos with different 3D and color systems and processed the obtained information to generate both virtual and physical output of the data.
Aside from recording a number of different tile designs that cover the walls of the ground floor and the staircase, digital technologies were also employed to digitise the incomplete wall paintings in the frescoes room at the first floor, to capture data for a prospective digital restoration project, as well as some of the great classic sculpture pieces from the collection.
Students experimented with how to digitally restore certain areas and envision ways in which the construction of conservation facsimiles could form a balance between the preservation of the site and the public interest in visiting it. They considered technology in a broader cultural, political and aesthetic context, informing their approaches with archival research, materials science research and other relevant research in order to address the range of issues discussed during the course.
Recording at Casa de Pilatos
Across three intensive days in October 2018, a team of experts from Factum Arte worked with the students in recording a selection of elements in the building (tiles, wood and plaster reliefs, marble sculptures, architectural spaces and frescoes) using a range of systems. This first phase of Factum Foundation's work at Casa de Pilatos aims to demonstrate the potential of digital recording technology to become an active force in the preservation of such a unique site.
Central to this initiative is the use of close-range recording methods to document Casa de Pilatos' most unique element: the tiles. For the first time, a selection of the tiles that adorn the walls were 3D-scanned in in high resolution, employing the Lucida 3D Scanner and close-range photogrammetry. Non-contact surface recording is becoming increasingly important for monitoring the conservation state of cultural artifacts and, in the case of Casa de Pilatos, the tiles can provide an insight into the building’s condition as a whole.
Photogrammetry was the preferred method for capturing relief and colour information of the tiles at the main courtyard. This involved recording a selection of tiles in sections of about 80×80 cm that represented the 120+ different design patterns present throughout the building. The method consisted of shooting at a distance of approximately 50 cm to the wall's surface, composing a matrix of rows and columns with high overlap among consecutive pictures. Each set of photographs was imported in specialist software like Reality Capture to create a highly detailed 3D model with colour texture. Due to the glazing of the tiles, it was necessary to use a cross polarization filter to reduce the slight shine on the photographs, which can result in inaccurate surface data.
After an initial training session by Factum Arte's Pedro Miró and Carleton University's Abhijit Dhanda, the students worked in pairs using a recording system formed by a camera with mounted flash light, fixed to a horizontal slide to facilitate the data capture. The progress of the recording sessions was adapted to the progression of the sun, choosing at each moment areas of the courtyard with no direct sunlight. By the end of the three-day session, a total of about 24 different tile patterns were recorded at the main courtyard.
While close-range photogrammetry was applied to record tiles sections at the courtyard, the Lucida 3D Scanner was used inside one of the adjacent rooms and the chapel as this method requires lower lighting levels. Lucida is a system designed and created through the collaboration of artist and engineer Manuel Franquelo, Factum Foundation, and our sister company Factum Arte. It has been specifically developed for the field of heritage conservation, to record the surface of paintings, maps, walls and other low-relief objects. Lucida provided the possibility of looking at the tiles at Casa de Pilatos from a unique point of view; focusing on their beautiful relief qualities without the distraction of colour.
The main advantage of the Lucida with respect to photogrammetry is that it can generally generate 3D information with a closer correspondence to the real surface, meaning with lower levels of noise and other artifacts; another advantage is that the 3D information is already scaled to the real dimension. On the other hand, the disadvantages are the slow recording time (about 4 hours for 1m2) and the fact that it cannot capture colour information.
Students worked in pairs operating the Lucida scanner in shifts. A section of 48×48 cm was recorded of each tile pattern in the room, resulting in a total of 12 different sections. Lucida can record the surface of objects by projecting a laser beam from a constant distance of about 10 cm; two video cameras record the distortions of the beam as the scanning head moves across the wall, converting the video footage in gray scale depth map information of the relief. This data can be used for digital fabrication (i.e. through CNC-milling) or for study, as a shaded render in combination with other layers, such as colour.
The wall areas in the room scanned with Lucida were also recorded with panoramic composite photography, in order to also obtain colour information of the tiles. This colour layer was then registered onto the shaded renders generated by Lucida, creating a multi-layered archive to accurately examine the tiles' current state of conservation. The layers can be viewed in incredible detail via multi-layered online browers through the following links: 1, 2, 3.
High-resolution surface information of the tiles obtained with Lucida and photogrammetry can prove particularly important for new forms of preservation of Casa de Pilatos. Apart from the vast possibilities for study and analysis of the tiles through this digital data, utilising software applications like the multi-layered browser, the data can also be used for re-materialisation. There is something unique about reproducing tiles from 1530s with 21st century technology. Like a sort of digital craft, the data obtained with non-contact recording systems can be 3D-printed through methods like Océ's Elevated Printing technology, a mould of a selection of individual tiles can be made as a result. At this point, digital technology is combined with traditional craft skills of tile-making to produce a restitution of specific tiles from Casa de Pilatos: not a theoretical design but particular azulejos each with their own character and features.
Casa de Pilatos houses one of the great private art and antiques collection in Europe. From Roman statues to Baroque paintings, the value and complexity of the collection stands as one of building's main attractions. Close-range photogrammetry was also used to record two of the most beautiful examples: the marble high-relief depicting Leda and the Swan, on display in the Frescoes room, and the Good Shepherd, presiding over the Chapel’s altar. The obtained data can be shared publicly through online platforms like Sketchfab, or be utilised to create facsimiles for conservation purposes
A Faro Focus 3D Scanner was used to record the main spaces of the Casa de Pilatos. The 3D data obtained by this type of equipment provided detailed information about the shape and dimensions of the building itself, which will prove incredibly useful when eventually combined with the close-range recordings of the walls (the Lucida and photogrammetry data). The recording focused on the main courtyard, adjacent rooms and the Chapel on the ground floor, the first floor Frescoes room, as well as the staircase. The students were first introduced to the processes behind this type of recording and then worked in groups to carry out successive captures throughout the building.
Finally, the Frescoes room at the first floor, which contains a cycle of wall paintings known as The Four Seasons, or The Triumph of Ceres, was recorded with panoramic composite photography by Factum Arte's Gabriel Scarpa. Three walls in the room were recorded in extremely high-resolution to obtain information for an eventual digital reconstruction of the missing fragments. The conservation state of the frescoes is uneven, and the majority has disappeared in half the walls area. A series of engravings depicting the Four Seasons, in what is a very similar subject to that of the frescoes, is also on display in this room. This information could eventually be of great value as a reference to fill the missing fragments as part of a digital restoration process.