A team from the Malta Centre for Restoration (MCR) has developed a process making it one of the first international institutions able to accurately survey archaeological and architectural sites using a unique combination of the latest technologies.
MCR's Thealasermetry approach was publicly launched at the International Workshop on Scanning for Cultural Heritage Recording organised by CIPA in Corfu earlier this month.
CIPA, the leading international organisation specialised in heritage documentation, is formed out of an alliance between the International Society for Photogrammetry and Remote Sensing (ISPRS) and ICOMOS, the International Council on Monuments and Sites.
Thealasermetry marries digital photogrammetry, laser scanning and theodolite Total Station to produce accurate, three-dimensional surveys of important cultural heritage sites to a level of detail and accuracy that has until now not been possible.
The MCR team, led by architect Claude Borg and Dr Joe Cannataci, demonstrated the efficacy of this technique as proven during surveys carried out at Ggantija and Kordin temples III, among other sites.
From the results published to date it appears that MCR is the first institution worldwide to have successfully carried out accurate hybrid surveys of megalithic temples of any sort and certainly of the geometric complexity of those found in Malta.
The development of Thealasermetry was communicated to CIPA last March and the results were accepted for publication in a peer-reviewed paper by architect Borg and Dr Cannataci entitled "Thealasermetry: a hybrid approach to the documentation of sites and artifacts", which the authors presented during the CIPA international symposium in Corfu.
Research on applications of digital techniques to cultural heritage by MCR started in 1999-2000 by Joseph Schiro and Dr Cannataci. Mr Schirò, then head of the Book and Paper Conservation Department and today MCR's director, experimented with still and moving digital photography for documentation of cultural heritage with a particular emphasis on rapid publication of detailed images of rare book-bindings.
Dr Cannataci, chairman of the MCR's Board of Governors and also head of the Law and Information Technology Research Unit within the Centre for Communications Technology at the University of Malta, started work on database design and integrated work flows for project management within cultural heritage.
By June 2000 Dr Cannataci started the MCR's first experiments with high-resolution digital photo-graphy in preparation for integration by software engineering with laser scan data. In 2001, Dr Cannataci was joined by the assistant director responsible for MCR's Documentation Divison, Architect Borg, who helped design solutions to integrate data collected during laser scans with that obtained through high-resolution digital photogrammetry.
Long months of intensive work were rewarded when the MCR team successfully devised and employed a methodology which, among other advantages, overcame a problem known as metric propagation error, which very often prevents laser scans from being accurately fitted together.
The MCR process, which has been designated Thealasermetry, was subjected to field tests at a number of sites and most recently, at Kordin temples III. Anastasia Anastasi, Ivann Borg, Saviour Delia, Mario Grech, Joanna Micallef Hili, Marcia Young and Ramon Zammit from MCR's Documentation Division worked rigorously (laser scans were also often carried out at night) between December 2001 and last August to ensure that Thealasermetry would be tested and further refined.
MCR was able to complete the development of the Thealasermetry process thanks to the co-operation of the Museums Department, the Restoration Unit of the Works Division of the Ministry of the Environment and Fondazzjoni Wirt Artna.
MENSI s.a. of France and Photarc of the UK both provided technical consultancy and training on different aspects of laser scanning and photogrammetry to MCR's staff while Manwel Magrin from the Works Division contributed greatly to training and testing on land surveying.
Thealasermetry is MCR's second important technology breakthrough within 12 months. It follows MCR's successful design and creation of the IKONOS project, which is the first international attempt at distance-learning in conservation through satellite-enabled video-conferencing. The technical infrastructure for IKONOS will be installed between next month and December with broadcasts and courses scheduled to commence in the first quarter of next year.
MCR is a partnership between the University of Malta and the Ministry of Education. The centre's mission, as defined by the Cultural Heritage Act 2002, is to become an international centre of excellence in the provision of training, education, research and practice of conservation and restoration of cultural heritage.