Last month, Vittorio Sgarbi, the Italian secretary of State for culture, flew to Afghanistan to look into the question of recreating the great Buddhas at Bamiyan, destroyed by Taliban iconoclasts in 2001.
English Heritage have put forward proposals for a redevelopment at the Stonehenge site that could include a full-scale replica of the monument.
The idea of replicating major historical monuments often produces a harsh critical backlash, usually centred around the belief that the authenticity of monuments is being devalued, historic accuracy compromised and that Disneyland is invading the world of heritage. These extreme views attract media attention, but the deep cultural changes that underlie these specific projects are rarely given serious coverage.
People queue up behind certain philosophical banners without monitoring the relevance of the philosophy to current conditions. It was William Morris who, for instance, propagated the idea that the authenticity of a building or monument was destroyed when it was restored or removed from its original site.
In a world where decay did not occur this would be totally acceptable, but in our world pollution and terrorism can completely destroy monuments. We can only be grateful to those authorities in Florence who replaced Michelangelo’s sculpture of David with a copy in 1910 and placed the original in the Accademia. As a result of their foresight the David still repays detailed study. Had it stayed outside, one only needs to examine other monuments and sculptures in Florence to see what damage would have been wrought by atmospheric pollution. The replica that now stands outside the Palazzo Signoria is a very good one and I cannot see that its being a replica alters its environmental impact nor devalues the originality of Michelangelo’s work.
Although the idea of creating replicas of threatened sculptures has a long history in Germany, France and Italy, in England the reverse is true. In this country we still expose our important sculptures to environmental damage and claim that we are maintaining authenticity. As there is no conservation treatment that will preserve stone permanently, a very crude alternative has been employed, which consists of coating original surfaces with mixtures of lime and sand. This not only blurs the original quality of the carving, but also imparts a deadening uniformity on our medieval sculpture.
At the Liverpool Conservation Centre we have been developing laser scanning techniques to record, replicate and reconstruct sculpture and the methods by which it is created. One of our main concerns is that the way sculptures and monuments are recorded currently is highly unsatisfactory. Much recording still relies on photographs and in some instances photogrammetry. Both systems rely on light to define form and surface and this means that some areas are always lost in shadow.
Laser scanning works in a very different way (see illustration). A fine line of laser light is projected onto the surface of an object and as the light source is moved the line distorts. The distortions are recorded by an offset video camera and turned into digital data. The data are transformed instantly into 3-D images on screen that can be turned and manipulated to view the subject from any angle. This data can also be transformed into machining data so that computer-controlled cutting machines can produce replicas in marble, stone and other materials.
Laser scanning cannot only be used to replicate sculpture; it can also be employed as a forensic tool to improve our understanding of worked surfaces. When we carried out some scanning on ancient cup and ring carvings at Ilkley Moor for English Heritage, archaeologists were excited by the information that was revealed. Although these stones had been carefully examined and photographed, it was only when they were scanned that linkages between some of the marks became apparent. Similar effects have now been noticed on the monument dubbed by the media as Woodhenge. Numerous tool marks have been identified by the English Heritage team that were difficult to record by conventional methods.
Recently we produced a large stone replica (93cm high) of the Anglo-Saxon carving known as the Bredon Angel, which dates from the eighth-ninth centuries. While applying a patina to the newly machined stone surface we noticed traces of feathers on the wings that were not so visible on the original.
So often people have dismissed this form of replica as inferior to the original and not worthy of study. But, in many instances, we may find that replicas help us to understand originals more easily.
But the accuracy of copies such as the Bredon Angel and the fact that they are created in a natural material does raise the issue of fakes. We have been aware of this for some time and our involvement with the technology is, in part, a response to the problem. The equipment used to create these replicas is readily available and unless museums understand how it can be used they will become the victims of it. Currently replicas are machined or moulded to an accuracy of 0.1mm. We have measured the accuracy of a really good copy carver and their best accuracy is 2mms, which is the resolution to which Rodin’s “practiciens” worked to. Some laser scanners can already record details to an accuracy of 0.2mm and the machining technology is moving ever closer to that resolution.
Scanning details from the works of a sculptor like Rodin could allow forgers to amalgamate highly convincing details (such as finger marks, tool marks etc) into new compositions that are totally convincing in all their details.
Once in the computer, objects can be enlarged, reduced, remodelled or reversed to make a pair. Data can be turned into machined replicas or into moulds to produce bronzes, plasters and terracottas. Shrinkage of materials, such as bronze and terracotta, can be compensated for so that replicas are exactly the same size as known originals in marble.
Although there is a need for the art world to become better informed about these technologies and we need to make some serious moves towards regulation, this should not obscure the benefits of the new technologies. Museums cannot allow visitors to touch originals; there is too much evidence of how harmful this can be. However, by producing high quality replicas we can allow visitors to handle sculpture made in marble or bronze. For young visitors it is particularly important that they come to appreciate works of art in a language they understand. To manipulate sculptures on screen, light them in different ways, to model copies of originals and to remove restorations brings them close to experiences that are normally restricted to the museum curator and conservator. For the blind, also, the opportunity now exists to handle replicas and to access 3-D electronic images of sculpture through touch-sensitive styluses.
These advances are now realities and they point to a much wider involvement with works of art as well as a more democratic approach to their availability. One of the major changes that has taken place recently in the way we view history, is that people are no longer content to look at ruins in fields; they need to see how the ruin looked before it decayed. Television programmes such as “Walking with dinosaurs”, “Meet the ancestors” and “Time team” have raised huge expectations and have also demonstrated the extraordinary potential of the new computer based technologies. In science and industry the value of working models for testing theory has long been understood. Archaeologists have now also adapted this approach and found that reconstructions not only reflect existing knowledge but can uncover new knowledge.
Originally appeared in The Art Newspaper as 'Identical copies of the Elgin marbles?'