Terrestrial laser scanning and close range photogrammetry for 3D archaeological documentation: the Upper Palaeolithic Cave of Parpalló as a case study

Graphic and metric archaeological documentation is an activity that requires the capture of information from different sources, accurate processing and comprehensive analysis. If monitoring of the state of conservation is required, this task has to be performed before intervention, during and after the completion of the works in a repetitive way. This paper presents the use of terrestrial laser scanning (TLS) in order to effectively produce, prior to intervention, accurate and high-resolution 3D models of a cave with engravings dating back to the Upper Palaeolithic era. The processing of the TLS data is discussed in detail in order to create digital surface models. The complexity of the cave required the integration of two techniques, TLS and close range photogrammetry to yield not only traditional drawings such as sections and elevations, but also photo-realistic perspective views and visual navigation worlds fully operational in 3D environments. This paper demonstrates the potential of integrating TLS and close range photogrammetry to provide both accurate digital surface models and photo-realistic outputs. This processed data can be used to systematically improve archaeological understanding of complex caves and relief panels of prehistoric art with tiny engravings.