RTI is a computational photography method that can provide outstanding high-fidelity photorealistic results in the documentation of surface textures. For works of art, RTI photography offers exceptional visual analysis of every surface relief detail providing great opportunities to revisit, challenge and revise old, as well as, new problems and phenomena in art history. This technology relies on extracting reflection information from several images of the same object lit from different angles. All images are captured from a fixed point within a “known” hemispherical coordinate lighting environment. These images are processed together with an algorithm that re-synthesizes the total reflection information into a new photorealistic representation. The final result has dynamic light properties, providing the user with the control of light on the surface of the photographed object. RTI images capture the surface texture of the painting panels, revealing impressive details of the artist’s painting technique and use of color pigments.
In the Heraklion Baptism of Christ painting, digital images demonstrate El Greco’s increased sensibility to the relief qualities of color pigment. He clearly utilized these attributes of his pigments to “mould” and animate parts of his composition. In addition, RTI images shed light on important details of the painting panel, such as the group of standing figures in the background setting of the represented scene, and the date in Latin numerals located in the lower left corner of the work. Furthermore, RTI documentation provides a detailed record of the state of preservation of the famous work that complements the analytical study of the painting led by the Benaki Museum and published in 2005.
The analysis of the View of Mount Sinai painting with the use of RTI images reveals interesting details of El Greco’s work in the way he painted the overall representation of Mount Sinai’s landscape, as well as the various figures in the lower foreground of the painting. Such close visual analysis provides an opportunity to revisit issues of composition, perspective and synthesis as well as to continue probing questions regarding the artist’s inspiration and influences. Moreover these images offer a clear visual understanding of the preservation condition of the painting and the visible evidence of damage and deterioration that it has suffered over time.
The imaging project was a collaborative effort between the Cyprus Institute’s ICACH (Imaging Center for Archaeology and Cultural Heritage) and the Historical Museum of Crete with the support of the European Project LinkSCEEM-2.