The rock, the whole rock, and everything about the rock : 3D-scanning of Bronze Age rock art sites in central-eastern Sweden using Leica MS60 and RTC360

The different documentation methods of rock art all have their pros and cons in recording petroglyphs. Traditionally it is the figurative content that has been in focus, but because Bronze Age motifs often relate to and incorporate the topography and mineral composition of the rock there is a need to also capture these aspects to a higher degree. The new 3D-techniques offer interesting possibilities to achieve this. Hitherto, handheld scanners and photogrammetrical approaches have been employed to record smaller areas of rock art but they are only rarely capable of capturing a larger part of an outcrop. To capture a fuller context of the petroglyphs, we have evaluated the potential of other types of 3D-scanners; a Multistation scanner, Leica MS60 and a dedicated dome-scanner, Leica RTC360, to record seven whole rock outcrops with rock art in central-eastern Sweden. Our tests conclude that although the scanners perform parts of the recording process differently, they both are capable of capturing even faint petroglyphs as well as the curvature and topography of a whole outcrop, including textures in colour.