180 ARCHAEOLOGICALILLUSTRATION
and three-dimensional images from survey information.
The use of CAD does not restrict one to working from
the keyboard or to inputting data ‘from scratch’. A scale
drawing made on the site may be entered into the com-
puter by placing the drawing on a digitizing pad (a sen-
sitized electronic drawing surface) and tracing carefully
with a pen-like instrument, or by importing the image as
a Bitmap and tracing it digitally within the software
package. Highly accurate two-dimensional drawings
have been produced in this manner from original draw-
ings. The relative height information can then be added
to produce three-dimensional images.
The effects of sag in a building or hogging influences
on a ship are readily apparent in three-dimensional per-
spective views whereas they are difficult to see in two
dimensions. The ability to rotate a structure or to change
perspective reveals features that would otherwise only be
obtainable through tedious re-drawing. This feature is
equally dramatic in the three-dimensional display of the
archaeological stratigraphic sequence. The surface contours,
strata, and artefacts can all be displayed in their original
spatial relationships. This level of representation allows
the archaeologist to analyse the site in ways not previously
available. Beyond the potential insights revealed by CAD
drawings, there is also a significant reduction in the
amount of effort required to reproduce graphics. CAD
software can replace the task of photographic reproduc-
tion, allowing the production of drawings of any size at the
press of a key.Interpretive drawings: Interpretive drawings, recon-
structions, views of objects as they might have been used
and objects placed together in assumed association have
their place in the depiction of archaeological evidence.
However, they should be rigidly separated from record
drawings, which are representations of the objects as they
are, not how it is thought they should be (i.e. observa-
tions not interpretations). Any element of a record draw-
ing involving hypothetical reconstruction (e.g. the shape
of missing sections of a pot) should be clearly indicated.
Of course, some reconstructions can be made with more
confidence than others, and such drawings can be fun-
damental to archaeological work in terms of communi-
cating ideas and exploring interpretations. It cannot be
overstated, however, that these types of illustration are not
an adequate sole record of an object.Figure 18.17 An orthographic view of the shaded 3-D laser-scan data of the Mary Rose(1545) hull. As the scanner
operates in a ‘line-of-sight’ manner, the timbers near the top have been obscured from the scanning viewpoint near the
ground. (Copyright Archaeoptics Ltd; reproduced courtesy of the Mary Rose Trust).
Further Information
Eiteljork II, H., Fernie, K., Huggett, J., and Robinson, D., 2003,
CAD: A Guide to Good Practice.Oxford.
Green, J., 2004 (2nd edn), Maritime Archaeology: A Technical
Handbook. London.
Griffiths, N., Jenner, A. and Wilson, C., 1990, Drawing Archaeo-
logical Finds: A Handbook.London.
Institute of Field Archaeologists, 2007, Draft Standard and
Guidance for Nautical Archaeological Recording and Reconstru-
ction. Reading (www.archaeologists.net).
Steiner, M., 2005, Approaches to Archaeological Illustration: A
Handbook. CBA Practical Handbook 18. York.