- EQI and 4DHeritage
How and why it is useful to document structures and spaces in 3D?
3D documentation can enable conservationists, teachers and students to explore structures in multiple dimensions – through time and also through different spectra. This can encourage a multidisciplinary approach to conservation, allowing the unseen to be revealed, and spaces to be experienced in ways never before possible.
This can transform stakeholder engagement as we have explored in an earlier blog. https://www.4dheritage.com/post/malian-heritage-experts-have-a-virtual-experience-of-djenne
Our experience of 3D documentation is that traditional approaches to physical modelling can complement the virtual models as explored in this blog https://www.4dheritage.com/post/why-print-a-digital-model
Dr Laura Basell of the School of Archaeology and Ancient History, University of Leicester @ArchAncHistLeic @leicesterstudythepast demonstrated the extraordinary detail that LIDAR scanning can capture from the Kidichi baths to the subterranean Mwanampambe cave, in Zanzibar.
The cave itself remains in active use as a shrine, with a local guardian, and there are objects in the deepest recesses of the cave. The cave name, Mwanampambe derives from the name of spirit thought to reside there.
The surviving range of Persian baths at Kidichi are the most ornate in Zanzibar and are notable for their elaborate plaster stucco decoration.
The images above show an aerial view of the baths as well as a 3D analysis of elevations of the structure and the site.
These sites were selected to demonstrate a range of archaeological methodologies, including ground penetrating radar (GPR), terrestrial laser scanning (TLS), unmanned aerial vehicle (UAV) and photogrammetry, to promote understanding of their utility in African contexts.
Prof Mark Horton of the Cultural Heritage Institute of the Royal Agricultural University in the UK described how UAVs and photogrammetry have transformed 3D capture of structures and sites in remote places, but also the challenges that remain, notably in recognising the limits of accuracy and resolution, artefacts created by the software used to knit the 2 D perspectives together to create a 3 D object, and the challenges of then co-registering independent datasets to layer additional information on the model.
All these techniques generate very large amounts of data which can quicky test data processing limits of conventional devices and / or data storage. This was illustrated by the example of the 3D UAV based survey of the Shali fortress.
The Model of the Shali fortress in the Siwa Oasis can be seen at https://skfb.ly/6VFFq. This simple 3D model is made of over 2.3m vertices and 4m triangles. It means that the site can be viewed from any perspective or height to reveal the full richness and detail of the site.
Viewed in real time, it requires a good broadband connection to view, but it can also be downloaded and viewed locally.
Such a model allows measurements to be made or provide a virtual model that traditional modellers can work with, or order to create a physical 3D museum or architectural exhibit.
The work of Ahmad Hariri in Jordan’s Za’atari refugee camp shows the potential value of such approaches both to celebrating the skills of local artists, but also documenting and sharing heritage sites. While in Zattari refugee camp, Ahmad Hariri set up an initiative in to recreate Syria’s heritage sites in miniature. His motivation was to inspire another generation “There are lots of kids living here who have never seen Syria or who have no memory of it” as he commented.
Hariri’s work as well as the Shali fortress projects show how digital documentation creates new ways of exploring a structure or place, enabling collaborative research, community outreach, education and advocacy – worldwide. However success requires careful planning and a multidisciplinary team who can cover both the technical aspects of the data capture – as well as the story that it tells.
This was illustrated in the concept developed by LSN working with Google Art and Culture and Inition to use augmented reality to bring alive a 3D model of the Great Mosque of Djenne to show how this building is not only unique from an architectural perspective, but how within the community it is at the centre of faith, learning, and local economy.
In the image above, the Great Mosque can be seen in the centre of the island city. As a building it highlights the richness of the island city’s history and living heritage.
The 3D model of the mosque.
Clicking on the above image will take you through to the immersive experience.
Increasingly we expect to see hybrid approaches which may include the accuracy of laser scanning, the richness and cost effectiveness of the drone based photogrammetry, and 360 imaging to provide an intuitive immersive experience.