The Balkan Heritage Foundation and Sofia History Museum partnered together to introduce the first in a series of RTI courses for museum curators. The hands-on training was led  by dr. Miglena Raykovska with the Institute of Information and Communication Technologies (Bulgarian Academy of Sciences) and adjunct professor in the Balkan and Eastern Mediterranean Archaeology (BEMA) program at New Bulgarian University. The RTI course involved the training of 10 museum workers along with the student – Melissa Helm in the BEMA MA program. It took place in the digital center of the Sofia History Museum in the period September 12 – 16, 2022.

The goal of the training was to teach museum specialists how RTI (Reflectance Transformation Imaging) can be used to assist in the examination and documentation of cultural heritage objects. The course included information about photographic equipment and setups and the steps to process and view images via the software. A total of sixteen artifacts from the collection of the Sofia History Museum were processed through RTI during the course of the training. They included a bronze coin, multiple ceramic sherds, a ceramic oil lamp and a bronze cross pendant among others, with the final object being a stone inscription from ancient Roman Serdica.

How RTI works?

RTI is a process that involves using technical photography and RTI computer software developed by Cultural Heritage Imaging (CHI), the main one being RTI builder. The builder combines multiple images by keeping track of the position of the light source from various angles in each capture. This results in  a high resolution image.

The camera is mounted on a tripod or dome, while a flash is moved in various positions throughout the image capture. The distance of the flash should remain consistent and the camera and the object must remain motionless during the process. The use of a dome helps to ensure this with little interference from the worker. Once the images have been run through the RTI builder, the processed image can then be viewed through the RTI viewer software. The RTI viewer has various digital enhancement settings to view the details of an object’s surface by using the highlights and shadows to better reveal information that can’t be seen by the naked eye. This method is particularly useful for reading inscriptions on ancient artifacts which have become illegible over time.

Photos: Anton Chalakov
Video: Melissa Helm