A PHOTOGRAPHIC DOCUMENTATION WORKFLOW FOR DIGITIZATION OF CULTURAL HERITAGE: THE 14 CENTURY CHURCH OF SV. NIKOLA IN KALOTINA, BULGARIA

Abstract. The church of Sv. Nikola, dated to the mid-14th century, is an important medieval cultural heritage monument with vivid fresco iconography located in the village of Kalotina, Bulgaria. The church consists of a small narthex and a larger naos with an apsidal wall. Much of the decorative details are beginning to degrade which makes the need for documentation of the current state important for preservation. Due to its remote location, public access is limited for both visitors and researchers. During the recent campaign, a workflow was designed with the purpose of obtaining complete documentation of the church. The workflow aimed to be low-cost and relatively quick. Complete photographic documentation was conducted including close-range photogrammetry of the interior and exterior of the church, Reflectance Transformation Imaging (RTI) of a selection of the graffiti within the frescoes, and 360-degree HDR panoramas. Additionally, a field survey of the surrounding area was performed by archaeologists and a geodetic survey which was used for the georeferencing of the photogrammetric 3D models. This detailed workflow developed for this project serves as a case study of a methodology for complete documentation of immovable cultural heritage.