3D LASER SCANNING OF HISTORIC MOLDS FOR DOCUMENTING THE RICHARD-GINORI FACTORY COLLECTION

Abstract

This paper illustrates the use of three-dimensional (3D) laser scanning to produce virtual models from plaster piece molds of the Richard-Ginori porcelain factory (Sesto Fiorentino, Italy). This study was carried out as part of a long-term project to document the artifacts of the factory including porcelain sculpture, models in wax, terracotta, and plaster, as well a collection of several thousand plaster piece molds dating from the mid-18th to the early 20th century. The objects contained inside the molds are often not recognizable as the molds are made up of several pieces and the internal surfaces are, of course, in negative. Previously, the identification of the molds’ subject matter has been limited to recasting porcelain models to produce positives. This time-consuming process can compromise the preservation of the molds. Virtual reconstruction using 3D laser scanning was applied to a set of plaster molds for a statuette called the Giant. Comparison of the virtual reproduction to the original model in terracotta demonstrated it was a faithful copy. The method described in this paper proves that identification of the subject and preservation of the molds are possible with numerous benefits over the traditional process for producing finished porcelain artifacts.

Résumé – Cet article présente l'utilisation d'un numérisateur laser en trois dimensions utilisé pour produire des copies virtuelles à partir de pièces de moules en plâtre de l'atelier de porcelaine Richard-Ginori (Sesto, Fiorentino, Italie). Cette étude fait partie d'un projet à long terme pour documenter la production de cet atelier, ce qui inclut des sculptures en porcelaine, des modèles en cire, en terre cuite et en plâtre, ainsi qu'une collection de plusieurs milliers de moules en plâtre datant du milieu du 18ème siècle jusqu'au début du 20ème. Comme les moules sont fabriqués par l'assemblage de plusieurs pièces dont les surfaces sont en négatif, l'identification des objets qui leur sont associés est difficile. Auparavant, l'identification du sujet d'un moule se limitait à la production d'un nouveau modèle en porcelaine. Ce procédé est long à mettre en œuvre et est potentiellement préjudiciable à la préservation des moules. Une reconstruction virtuelle d'un ensemble de moules en plâtre d'une statuette intitulée «Le géant» a été effectuée à l'aide d'un numérisateur 3 D. La comparaison de la reproduction virtuelle avec le modèle original en terre cuite a démontré la fiabilité du procédé. L'approche présentée dans cet article confirme que l'identification du sujet et la préservation des moules est possible et que cette approche possède plusieurs avantages lorsqu'on la compare au procédé traditionnel pour la reproduction des objets en porcelaine.

Resumen – Este trabajo ilustra el uso de escaneo con láser tridimensional (3D) para producir modelos virtuales a partir de moldes de yeso de la fábrica de porcelanas Richard-Ginori (Sesto Fiorentino, Italia). Este estudio fue llevado a cabo como parte de un proyecto a largo plazo para documentar los artefactos de la fábrica, incluyendo escultura en porcelana, modelos en cera, terracota y yeso, así como una colección de varios miles de moldes de piezas de yeso que datan de mediados del S XVIIIs. 18 hasta principios del s. 20S XX. Los objetos contenidos en el interior de los moldes a menudo no son reconocibles, debido a que los moldes están hechos de varias piezas y a que las superficies internas están, por supuesto, en negativo. Previamente, la identificación del tema los temas de los moldes había estado limitada a vaciar nuevamente los moldes de porcelana para producir positivos. Este proceso consume mucho tiempo y puede comprometer la preservación de los moldes. Se aplicó la reconstrucción virtual usando de escaneo con láser 3D a una serie de moldes de yeso para una estatuilla llamada el Gigante. Las comparaciones de la reproducción virtual con el modelo original en terracota demostraron que es una copia fiel. El método descrito en este trabajo demuestra que la identificación del tema y la preservación de los moldes es posible, con numerosos beneficios sobre el proceso tradicional de producción de artefactos terminados de porcelana.

Resumo – Este artigo ilustra o uso do escaneamento a laser tridimensional (3D) para produzir modelos virtuais a partir de moldes de peças de gesso da fábrica de porcelana Richard-Ginori (Sesto Fiorentino, Itália). Este estudo foi realizado como parte de um projeto de longo prazo para documentar os artefatos da fábrica, incluindo escultura de porcelana, modelos em cera, terracota e gesso, bem como uma coleção de vários milhares de moldes de peças de gesso que datam desde meados do século XVIII até o início do século XX. Os objectos contidos no interior dos moldes muitas vezes não são reconhecíveis, uma vez que os moldes são feitos de várias peças e as superfícies internas estão, é claro, em negativo. Anteriormente, a identificação do tema dos moldes tinha sido limitada à remodelagem de moldes de porcelana para produzir positivos. Este processo extremamente demorado pode comprometer a preservação dos moldes. A reconstrução virtual usando o escaneamento a laser 3D foi aplicada a um conjunto de peças de moldes para uma estatueta chamada O Gigante. A comparação da reprodução virtual com o modelo original em terracota demonstrou que ela era uma cópia fiel. O método descrito neste artigo revela que a identificação do tema e a preservação dos moldes são possíveis com numerosos benefícios sobre o processo tradicional para a produção de artefatos de porcelana com acabamento.

Keywords:

• 3D laser scanning
• Virtual model
• Plaster molds
• Artistic porcelain
• Richard-Ginori factory

Acknowledgments

The authors would like to express their thanks to Benedetta Adembri, inspector of Soprintendenza dei Beni Culturali del Lazio for her important suggestions, to Oliva Rucellai, curator of Museo Richard-Ginori della Manifattura di Doccia, and to Associazione Amici di Doccia for their important contributions to this paper. The authors are also grateful to Marquis Lionardo Lorenzo Ginori Lisci, who allowed them to consult his family archives and to Elena Mattioli, who assisted them in their research in the archives.

Sources of Materials

•	3D Scanner HD acquired from http://www.nextengine.com (accessed 11/18/2013)
•	ScanStudio HD PRO, software upgrade to the standard ScanStudio HD, acquired from http://www.nextengine.com (accessed 11/18/2013)
•	Blender Software free download from http://www.blender.org/ (accessed 2/11/2014)
•	Meshlab Software free download from http://meshlab.sourceforge.net/ (accessed 2/11/2014).

Additional information

Notes on contributors

Rita Balleri

Rita Balleri received her M.A. in Art History from the University of Florence under the supervision of Prof. Mina Gregori. In 2011 she was awarded a doctorate from the same university for a thesis on the sculptures acquired by Carlo Ginori and his son Lorenzo. For the past few years she has collaborated with the Richard-Ginori Museum of the Doccia Manufactory in Sesto Fiorentino (Florence). In 2005 she was awarded a scholarship from the Fondazione di Studi di Storia dell'Arte Roberto Longhi Firenze in which she focused on the interest in classical antiquity in the 18th century. Currently she is a research fellow at the University of Florence and is working on the project for cataloguing the historical molds at the Richard-Ginori Manufactury. Address: Information Engineering Department - University of Florence, Via S. Marta, 3 – 50100 Florence, Italy. Email: [email protected]

Sergio Di Tondo

Sergio Di tondo graduated in Architecture in July 2004. From 2005 to 2008 he taught digital survey and computer graphics at the University of Florence and abroad. In 2008 he received his Ph.D. from the Department of Architecture of the University of Florence. From 2007 to 2012 he was assistant professor at the Department of Architecture in Florence. From 2010 to 2011 he was a research fellow at the same University. Since 2009 he has been conducting research on virtual reconstruction of architectural friezes of the Maritime Theatre and the Piazza d'Oro in Hadrian's Villa. Since 2006 he has worked freelance in digital survey technologies and representation applied to cultural heritage and other areas. Address: University of Florence - Piazza Ghiberti, 27 - 50100 Florence, Italy. Email: [email protected]

Giulia Adembri

Giulia Adembri graduated in 2003 in Telecommunications Engineering at the University of Florence. From 2003 to 2012 she worked in the Department of Electronics and Telecommunications (University of Florence) on national, European and international research projects in several subjects: technologies for cultural heritage, intelligent transport systems, safety & security (software validation SIL4), and satellite environmental remote sensing. Currently she is part of the research team that took over the project for cataloguing the historical molds at the Richard-Ginori Manufactury. Address: ICON c/o IUF, Via Madonna del Piano 6, 50019 Sesto Fiorentino, Florence, Italy. E-mail: [email protected]

Monica Gherardelli

Monica Gherardelli received her degree in Electronic Engineering from the University of Florence in 1981 and, in 1987, a PhD in Information Engineering from a Consortium of the Universities of Padua, Florence, Pisa, and Trieste (Italy). From 1981 to 1991 she worked on research pertaining to polarimetric radars. Since 1991 she has been Associate Professor at the Department of Engineering, first with the University of Aquila, Italy and then with the University of Florence. Her current research focuses on remote sensing, digital transmission and elaboration, and application of digital technologies to cultural heritage. Address: Information Engineering Department, University of Florence, Via S. Marta, 3-50139 Florence, Italy. Email: [email protected]