Towards Three-Dimensional Non-Invasive Recording of Incised Rock Art

By Simpson, Alice; Clogg, Phil et al. | Antiquity, September 2004 | Go to article overview
Save to active project

Towards Three-Dimensional Non-Invasive Recording of Incised Rock Art


Simpson, Alice, Clogg, Phil, Diaz-Andreu, Margarita, Larkman, Brian, Antiquity


Traditional recording methods and problems associated with them

Recording is the essential prerequisite of any database compiled for research and conservation programmes for rock art. In the British Isles several methods have been employed which can be grouped into two major categories: two-dimensional and three-dimensional recordings. The first one includes techniques already in use in the nineteenth century such as free hand drawing and casts, and others appearing later: tracing, rubbing (Beckensall 1983: 32), photographs and digital image processing (Donnan 1999). Three major problems affect these techniques. Firstly, they document in two dimensions what are essentially three-dimensional surfaces and volumes which usually results in inaccuracies that can sometimes be important (Figure 1, see also Coles 2003). A second major problem, as Loendorf has recently highlighted, mentioning rubbing in particular, is that it is proven to have a damaging effect in samples taken for dating (Loendorf 2001: 57). Given the difficulties with dating engravings experienced in Foz Coa (Zilhao 1996) this is a problem liable to affect British rock art in the future, even if it does not now. Finally, casting, tracing and robbing are invasive techniques and may affect rock art preservation. Although in his article on recording Loendorf considers invasive techniques (especially in this case tracing) as potentially harmful, he acknowledges petroglyphs are usually more durable. However, this is not always the case, as the condition of some rock art surfaces in Britain (such as Achnabreck) shows. Preservation is a major concern. In the main report of the Rock Art Pilot Project commissioned by English Heritage, photography was recommended as a non-invasive technique (RAPP 2000: 88). Historic Scotland follows a policy of non-contact techniques for recording rock carvings (Yates et al. 1999).

[FIGURE 1 OMITTED]

The second category of techniques used in recording prehistoric carvings in the British Isles comprise those recording in three dimensions: laser scanning (Eklund & Fowles 2003) and three-dimensional modelling from photographs. Both are still in an experimental stage. They have the advantage of overcoming the problems associated with 2D recording mentioned above and require no contact. Despite the potential of laser scanning, it is still a high cost option and therefore the opportunity for its use is currently restricted. 3D modelling from photographs, however, is more accessible at low cost. In order to investigate its potential a programme of study was established at the Department of Archaeology, University of Durham, England. The aim of the project wig to test the feasibility and accuracy of a method of recording rock art in 3D, in order to maintain the "real-world" spatial relationship between motifs overcoming the inaccuracies of 2D recording.

3D recording of the Horseshoe rock

Relatively inexpensive commercial software, mostly based on single camera photogrammetric techniques, is now available for creating precise 3D models from photographs. Photomodeler (produced by Eos Systems, Canada) is an example of such a programme and its use is illustrated in a number of archaeological examples on the manufacturers website. (www.photomodeler.com and www.3dphoto.dk), in England a project developing methodologies for 3D visual representations of megalithic monuments was also based on the use of a previous version of Photomodeler (Gillings 2000). The study presented here is an investigation into the suitability of Photomodeler (version 4) for the recording of rock art.

Photomodeler uses identifiable points within a series of overlapping photographs to calculate the position of the camera. If the characteristics of the camera and lens combination are known, then the 3D co-ordinates of those points can be determined and a wire frame model can be constructed. Visual detail can then be laid over the wire-frame model from photographs taken without the control points.

The rest of this article is only available to active members of Questia

Sign up now for a free, 1-day trial and receive full access to:

  • Questia's entire collection
  • Automatic bibliography creation
  • More helpful research tools like notes, citations, and highlights
  • Ad-free environment

Already a member? Log in now.

Notes for this article

Add a new note
If you are trying to select text to create highlights or citations, remember that you must now click or tap on the first word, and then click or tap on the last word.
Loading One moment ...
Project items
Notes
Cite this article

Cited article

Style
Citations are available only to our active members.
Sign up now to cite pages or passages in MLA, APA and Chicago citation styles.

Cited article

Towards Three-Dimensional Non-Invasive Recording of Incised Rock Art
Settings

Settings

Typeface
Text size Smaller Larger
Search within

Search within this article

Look up

Look up a word

  • Dictionary
  • Thesaurus
Please submit a word or phrase above.
Print this page

Print this page

Why can't I print more than one page at a time?

While we understand printed pages are helpful to our users, this limitation is necessary to help protect our publishers' copyrighted material and prevent its unlawful distribution. We are sorry for any inconvenience.
Full screen

matching results for page

Cited passage

Style
Citations are available only to our active members.
Sign up now to cite pages or passages in MLA, APA and Chicago citation styles.

Cited passage

Welcome to the new Questia Reader

The Questia Reader has been updated to provide you with an even better online reading experience.  It is now 100% Responsive, which means you can read our books and articles on any sized device you wish.  All of your favorite tools like notes, highlights, and citations are still here, but the way you select text has been updated to be easier to use, especially on touchscreen devices.  Here's how:

1. Click or tap the first word you want to select.
2. Click or tap the last word you want to select.

OK, got it!

Thanks for trying Questia!

Please continue trying out our research tools, but please note, full functionality is available only to our active members.

Your work will be lost once you leave this Web page.

For full access in an ad-free environment, sign up now for a FREE, 1-day trial.

Already a member? Log in now.

Are you sure you want to delete this highlight?