3rd meeting of young researchers at UP 1 - IJUP - Universidade do ...

New Digital Methods on Rock Art Recording
Fusion of 3D Scanning with Multi-Spectral Images
Paulo Campos de Lima 1
1 Bolseiro BII do Centro de Estudos Arqueológicos das Universidades de Coimbra e Porto; Student of
Faculty of Letras, University of Porto, Portugal.
Nowadays, there’s a general knowledge of the problems concerning the study of Rock Art,
often consisting in the difficulty to see the paintings and engravings, as well as in the
limitations presented by the traditional recording method.
The usual method, which is based on paintings manual tracing and acrylic film printing is
dependent on the threshold and spectral acuity of the human sight and on the operator’s
subjectivity. In addition, it provides a poor adaptation to the tri-dimensional morphology of the
graphisms’ support, reducing its record to a flat two-dimensional projection that distorts both
the artworks’ internal spatial relationship and its relationship and distribution through the
support. At last, the frailty and size of the record which results from the application of this
method, creates a difficulty both on its handling by the investigator and on the storage and
conservation, factors that strongly influence its access.
Here, a new method is proposed, involving the use of non- intrusive digital technologies. These
are the result of the combining of multi-spectral photographic techniques which use a
combination of the light’s visible spectrum with the Near Infrared (NIR) and the Ultra-Violet
(UV), articulated with three-dimensional scanning of structured light (VTLE). The application
of these non-intrusive digital techniques at Rock Art record eliminates the physical contact of
the recording media with the graphics and, at the same time, fill some of the human sight
spectral and visual acuity limitations. Moreover, it eliminates the operator’s perception
subjectivity. In addition, it will also provide a tri-dimensional photo-textured digital model
which can be easily handled by the investigators, giving them accurate access to the artwork’s
spatial relationship, and to its relationship with the morphology as well as to its distribution
trough the support.
3 rd meeting of young researchers at UP 67