The experience of 3D structured illumination scanning of rock images

The methods of rock art study constantly develop. The petroglyphic occurrences on the rock surfaces contain the thousands of images, related to different chronological spans. New approaches of petroglyphs fixation, based on digitalstill information technology, added the traditional methods of documentation of the figures. The methods of 3D scanning permit to get the model of petroglyph and its surrounding in digital form, which can be applied for further computer processing and studying. The 3D models of petroglyphs are well-behaved for classification and systematization of the petroglyphic forms, use-wear research, extended comparison study, copying and etc. We present here the technology of 3D-structured illumination scanning and its possibilities as exemplified by the use of RangeVision outfit. We describe here the specifics and superiorities of this method in comparison with technology of photogrammetry. The authors of this study had analyzed the experience of 3D scanning of petroglyphs, carried out at the Sook Tyt the archaeological site (Republic of Altai) in 2015. Experience has demonstrated that the creation of 3D model is less labour-intensive process than method of photogrammetry. The article considers the work stages in the field: moving-in and adjustment of equipment, conditions and time of autonomous battery life, and elements of post-processing in the lab, such as panorama merge, the noise effect removing, texture mapping. We consider the possibilities of model visualization, including the arrangement of illuminants, which the clearly marked out the image. As a result, we have gotten the models of multifigured compositions with images of the Bronze Age wains and hunting scenes with deer in themanner of deer stones. The authors present the screenshots of 3D scenes with use of software filters for enhanced visions of received compositions.