Reflectance Transformation Imaging (RTI) on a Wooden Door and Sea Shells Decoration at the Immaculate Conception Parish, Guiuan, Eastern Samar
Students from the University of Melbourne Saiful Bakhri, Sophie Russell and Mark Barnes, and conservator Dr Nicole Tse with Anna Carlos and Jim Vasquez from the National Museum of the Philippines, conducted Reflectance Transformation Imaging (RTI) on cultural heritage at the Immaculate Conception Parish in Guiuan, Eastern Samar.
RTI and its versatility
Reflectance Transformation Imaging (RTI) developed by Cultural Heritage Imaging is a computational photographic method that records an cultural objects’ surface shape and colour, allowing the interactive re-lighting the objects from any direction. Today’s RTI software can be downloaded from Cultural Heritage Imaging www.culturalheritageimaging.org.
RTI is a very useful technology for recording objects in high detail. The light from the camera flashing at different angles reveals lines, holes, brush strokes and other details that may not be visible with normal photography. RTI images can make objects look ‘3D’ without the need for 3D modelling software.
Recording cultural objects, paintings and buildings is an important part of maintaining our cultural heritage. This might include writing condition reports, taking photographs or keeping lists. RTI scanning is another way we can record important cultural heritage with high detail. This means we have a digital record of the object that we can safely archive for future use. If the cultural heritage becomes damaged or destroyed, we can use the RTI scan to recreate, rebuild or reconstruct as close as possible to the original. It may even be possible to 3D print smaller objects. RTI scans can also reveal details in craftsmanship, patterns or damage that we cannot see with our eyes alone. Lastly, RTI images are a great way to engage people with cultural heritage, especially if they cannot visit the heritage in person.
Capturing the Wooden Door
The Immaculate Conception Parish in Guiuan, Eastern Samar has several large, carved wooden doors. Unfortunately, flood water caused damage to some of these doors during Typhoon Haiyan in 2013. Wooden objects like these are also vulnerable to pests such as termites and mould. In 2018 the National Museum and the Parish decided to create a fibreglass cast of one half of a set of doors from the south western entrance of the church, which local wood carvers Alfredo Menosa and Eric can later use to carve a new door. The door has intricate carvings showing plants, flowers, angels and fish. It was decided to RTI scan the door because as it is made of wood, it sits facing the outside of the church and it is immovable during a natural disaster it is particularly vulnerable to damage.