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Lo más destacado:• Se presenta una reproducción virtual de cuevas paleolíticas con grabados y pinturas de calidad que combina técnicas fotogramétricas y topográficas.• La metodología de trabajo fotogramétrico permite alcanzar una reproducción fiel tanto de la geometría como de la apariencia de las cuevas.• Se apuesta por la divulgación mediante técnicas de realidad virtual inmersiva y métodos interactivos de visualización. Abstract:We present three case studies illustrating the virtual reproduction of caves that belong to the most important artistic ensemble of the Paleolithic from Bizkaia (Spain): Benta Laperra, Askondo and Lumentxa. The complex morphology of the cavities, the fineness of their engravings and the poor definition of their paintings imply technical difficulties to achieve faithful reproduction of their geometry and appearance. The methodology applied in these caves, based on a combination of photogrammetric and surveying techniques, allows the creation of a complete virtual replica, without shadow zones and a detailed reproduction of their engravings and paintings. At the same time, this replica has given rise to a type of technical documentation that very faithfully and objectively facilitates the analysis and interpretation of the cave. On the one hand, series of longitudinal and transverse sections have been generated, extracting information of the cut profile and the projection of the surfaces through orthoimages of elevation-section with a level of resolution of 2 mm per pixel, equivalent to a scale of representation 1/10. In addition, the georeferencing of the caves has allowed the research team to generate cartography of elevations of floor and ceiling by means of contour lines and to overlap the cartography of the National Geographic Institute (IGN) to measure the distance that separates the ceiling of the cave from the external surface. It can be used to detect critical points that must be taken into account in case of possible actions in forestry or infrastructure projects. Finally, these virtual replicas allow the dissemination of a wealth in detail, through new interactive methods of visualization and virtual reality. In conclusion, the presented methodology means an advance with respect to the existing techniques thus providing solutions for both technical and informative applications.Keywords: virtual archaeology; 3D reconstruction; close-range photogrammetry; orthoimage; parietal art; surveying Resumen:Presentamos tres casos de estudio que ilustran la reproducción virtual de las cuevas pertenecientes al conjunto artístico más importante del paleolítico en Bizkaia (España): Benta Laperra, Askondo y Lumentxa. La compleja morfología de las cavidades, la finura de sus grabados y la poca nitidez de sus pinturas suponen dificultades técnicas para lograr la reproducción fiel de su geometría y apariencia. La metodología aplicada en estas cuevas, basada en una combinación de técnicas fotogramétricas y topográficas, permite la creación de una réplica virtual completa, con inexistencia de zon...

La museología es hoy en día un área de conocimiento en plena renovación y expansión, mediante la incorporación de nuevos métodos expositivos y didácticos que pueden ser utilizados por el profesorado en las aulas, dadas sus especiales características, para acercar el objeto directamente al sujeto, a la que están dedicados numerosos estudios, que abarcan los campos del arte, la historia, la arqueología o la educación.

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Software tools for photogrametric and multi-view stereo reconstruction are nowadays of generalized use in the digitization of architectural cultural heritage. Together with laser scanners, these are well established methods to digitize the three-dimensional geometric properties of real objects. However, the acquired photographic colour mapping of the resulting point clouds or the textured mesh cannot differentiate the proper surface appearance from the influence of the particular illumination present at the moment of the digitization. Acquisition of the actual surface appearance, separated from the existing illumination, is still a challenge for any kind of cultural heritage item, but very specially for architectural elements. Methods based on systematic sampling with commuting light patterns in a laboratory set-up are not suitable. Immovable and outdoor items are normally limited to the existing and uncontrolled natural illumination. This paper demonstrates a practical methodology for appearance acquisition, previously introduced in (Martos and Ruiz, 2013), applied here specifically for the production of re-illuminable architectural orthoimages. It is suitable for outdoor environments, where the illumination is variable and uncontrolled. In fact, naturally occurring changes in light among different images along the day are actually desired and exploited, producing an enhanced multi-layer dynamic texture that is not limited to a frozen RGB colour map. These layers contain valuable complementary information about the depth of the geometry, surface normal fine details and other illuminationdependent parameters, such as direct and indirect light and projected self-shadows, allowing an enhanced and re-illuminable ortoimage representation.