1gool,
uven,
d. -
w of the
include
build a
here the
lesirable
cas they
be more
thereof,
adopting
y fail to
ularities.
to be in
opular in
nrealistic
a false
| models
:defined,
precisely
E tiles or
ations in
effect in
ration of
leave out
petuating
- original
ich color
oloration
e is not
1 certain
| guess at
(Barcelo,
t gave a
ly has to
example
International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Vol XXXV, Part BS. Istanbul 2004
of how widely such hand-drawn reconstructions could be
(Müller, 1966).
In this paper, we want to build a case for detailed
reconstruction. Often more is possible than building sketchy
representations and one can go as far as virtual anastylosis, with
additional ‘repairs’ that are unacceptable if carried out for real.
We take a nymphaeum (monumental fountain) at the ancient
city of Sagalassos as a case in point. Technology is now
available to produce such reconstructions with relative ease and
at reasonable cost. Huge costs and efforts involved in producing
high quality models may actually have often been the initial
reason for not going further in the level of detail
and visual realism. Principled objections against such models
may sometimes have come rather as an afterthought. Also, in
the case of the Sagalassos nymphaeum that we present as a case
in point here, it is important to realise that the plan to produce a
physical reconstruction has helped greatly in ensuring that as
many parts as possible have been retrieved and put into context.
Virtual reconstruction technology will make similar care in
excavations worthwhile in cases where physical restoration is
not attempted.
Moreover, we believe maximally detailed, virtual reconstruction
to be well in line with international guidelines, whereas physical
reconstruction would only be so in the rarest of cases, when an
anastylosis project is possible. Even if the latter is possible, it
remains a very time consuming and expensive option.
e Following the ICOMOS (ICOMOS, 1999)
"Managing Tourism at places of heritage significance
(10/99) it is important to make a visitor's experience
‘worthwhile, satisfying, and enjoyable! (Principle 3).
Realistic reconstructions can greatly increase the level
of understanding and involvement. This argument
quickly gains importance as new generations are getting
used to impressively realistic images in movies and
games. How enticing can a simplistic model be to them?
e Detailed reconstructions can also help to realise the
Charter's Principle 6, that insists to 'relieve the
pressures on more popular places by encouraging
visitors to experience the wider cultural and natural
heritage characteristics of the region or locality’. By
offering virtual reconstructions, sites or monuments
with a lower degree of physical reconstruction can be
made more attractive. Reconstructions at Knossos may
not be among the archaeologists’ favourites, but they
definitely are a big hit with the general public. How to
turn other sites into similar success stories without
equally far-reaching physical interventions if not
through exciting virtual models?
* Also the Council of Europe Convention (Convention,
1985) for the Safeguarding of European Architectural
Heritage (Grenada, 10/85) calls for efforts to make
visits enjoyable, and emphasises that information and
sensibilisation policies should be based on the latest
technologies for communication and animation (Art. 15,
Art. 17.3). As we will argue, both computer vision and
computer graphics have progressed to a degree that they
can provide strong support to such endeavours.
e Such technologies can also help to
relieve the tension between making heritage accessible
and enjoyable for the visitors on the one hand, and the
guideline that physical restoration should be minimal,
i.e. only those parts ought to be reconstructed physically
for which there is no uncertainty and where sufficient,
original components are still available and are not
occluded by constructions at a later era. Modern
additions should be clearly recognisable as such. The
latter principles are stated in the Venice Charter
(Venice, 1964) for the Conservation and Restoration of
Monuments (Art. 9, 11, 15). These guidelines tend to
'spoil' the experience a visitor may want to have, but
virtual reconstruction can make up for this ‘loss’, and go
beyond.
e The Fname charter (Art. 19) possibly yields the
strongest support for detailed reconstruction: ’The
construction of 3D computer reconstructions and Virtual
Reality environments should be based upon a detailed
and systematic analysis of the remains, not only
from archaeological and historical standpoints but also
from close analvsis of the building materials, structural
engineering criteria and architectural aspects. Together
with written sources and iconography, several
hypotheses should be checked against the result
and data, and 3D models, ‘iterated’ towards the most
probable reconstruction.’ (Ename, 2002)
2. THE VIRTUAL ANASTYLOSIS OF A BUILDING
2.1 Overview
In the introduction, we have defended efforts to produce
detailed 3D reconstructions. Here we report on the 3D
reconstruction of one particular building, which poses a number
of interesting challenges. This is the nymphaeum (ornamental
fountain) at the upper agora of the ancient city of Sagalassos,
about 100 km to the north of modern Antalya.
DUE GARA Brack Ses 3 NC DI GEORGIA
grs e T 240 #8 ALIS
* x
: Sameun® . Hope
„Kosaslı ion
- dent) Tranaow
HE Gem
usa
. * ANKARA Sas ; "Erzurum
Baisaait Exkigshir * yer
"m
^snisa et
4 e Anatelia „Kayser
frm Sagalassos
Hema Dripartaios 4
m Kahramenmerss,
— Sank Urs ete
o Antbys k»€ Adars CSSS seit, x
* A "I * ^ t
= Mer, T.
iskendatua | {
4 SYRIA x iRAGD
EVEL !
Figure 1. Sagalassos in southern Turkey
The excavations at Sagalassos are among the largest
archaeological projects that are ongoing in the Mediterranean.
The site is extremely interesting, as Sagalassos was a
prosperous city from early Hellenistic times until it was struck
by a devastating earthquake in the 7th century. After having
been inhabited for more than thousand years, the city was
abandoned and disappeared into oblivion. The nymphaeum was
erected during the Roman era of the city, more in particular
during the reign of emperor Marcus Aurelius (AD 161-180).
