Rock group captures carvings

A new imaging technique developed by SINTEF is helping archaeologists to find, interpret and conserve rock carvings in digital format.

Archaeologists and Information and Communication Technology (ICT) researchers are using a technology called ‘structured light’, a method that quickly and easily reads the 3D shape of an object with the aid of a camera and a video projector. The images are transferred to a computer, which constructs a detailed 3D model of the object.

Kalle Sognnes, a professor of archaeology at Norwegian university NTNU, believes that the new method will arouse the interest of archaeologists everywhere, not least because the imaging technique helps researchers to see more than the human eye can manage alone. The method will make it easier to reveal scratches that otherwise would have been difficult to see.

In many rock-carving fields, scratches have been made at several levels on the same spot, which means that a rock carving may hide another older one lying below it. Going ‘into depth’ with the computer model makes it possible to identify, for example, whether the carvings have been made using different types of tool or with different techniques, and thus during different epochs.

Structured light makes it possible to retain the three-dimensional characteristics of rock carving for the future, using relatively inexpensive, portable equipment.

‘We know that other archaeology groups have tried to do the same thing with less advanced laser equipment. Such equipment is time-consuming to use, and it is not easy to bring it out into the field,’ says Sognnes.

This method of imaging and processing data from ancient monuments will make it possible to produce virtual exhibitions on the Internet, or to feed data directly into a milling machine to produce exact full-scale copies of the originals.