University of Malta (UM) Senior Lecturer Charlene Vella and her team have loaned a cutting-edge infrared (IR) camera in order to study a number of paintings in Malta that have rich historical value, includes ones from the 14th and 15th centuries.

This came as UM collaborated with Opus Instruments, a leading provider of IR imaging technology, loaning its Apollo IR reflectography (IRR) camera to Dr Vella, who forms part of the university’s Department of Art and Art History. The camera, loaned to the team for two weeks, was operated by Andrea Luca Bartolo, a graduate in Art History and a Master of Science in Conservation candidate from the Department of Conservation and Built Heritage.

The camera enabled the academics to meticulously photograph over 20 artworks, offering insights into their manufacturing techniques, particularly into their underdrawings – the preparatory sketch done on the surface prior to a painting – often visible through painted layers through the detection of reflected IR waves.

The Apollo IRR camera capturing "St Paul Polyptych"

One of the most importance masterpieces documented through the Apollo was the “St Paul Polyptych,” a late Gothic altarpiece located at the Metropolitan Cathedral Museum in Mdina. The Catalan artwork was executed in the late 14th or early 15th century and had previously stood as the old Mdina Cathdral’s titular altarpiece. It had been commissioned directly from Catalonia, and consists of 11 panel paintings narrating scenes from the life of St Paul the Apostle. The research was made possible thanks to Reverand Edgar Vella and his team at the Mdina Museum.

The Opus Apollo camera, renowned for its unparalleled precision and fidelity, operates through the use of an internal InGaAs area sensor with a spectral sensitivity of wavelengths between 900 and 1,700 nanometres, thus providing high-resolution images of up to 26 megapixels, boasting over 65,000 grey levels. Such images allow for various aspects of paintings to be studied, including underdrawings, compositional changes, brushwork, later interventions, and pigment transmission at different wavelength bands. Through the automatic stitching of thousands of photographed tiles and adjustable histograms, the usability and quality of the captured data is enhanced.

A painting (left) and an image of the same painting captured by the Apollo IRR camera

Dr Vella stressed the significance of the project, stating that: “Malta boasts a rich artistic legacy that spans centuries, and it is imperative that we employ the latest advancements in technology to study and preserve these invaluable treasures.”

“The loan of the Opus Instruments Apollo camera marks a significant milestone in our efforts to documents Maltese art for research purposes and more,” she continued.

Hannah Conway-Laws, Business Development Manager at Opus Instruments, expressed her enthusiasm about the collaboration with UM.

The Apollo IRR camera capturing the image of a painting

“The Apollo camera represents the pinnacle of IR imaging technology, and we are confident that its capabilities will greatly enhance the conservation efforts on Maltese masterpieces,” she affirmed.

Through the collaboration, both Opus Instruments and UM are aiming to continue advancing the field of cultural heritage preservation and technical art history. The two-week loan was facilitated by Pierre Bugeja, Founder and Senior Conservator of PrevArti Ltd, who loaned equipment through which the scans were made possible.

The 2024 IEEE International Conference on Metrology for Archaeology and Cultural Heritage, a conference on how technology can be used to preserve and study cultural heritage, will be organised in Valletta between 7th and 9th October 2024. For more information, click here.