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PHOTOGRAMMETRIC REPRODUCTION
OF THE MAP OF MEXICO 1550
M. Nuikka®, L. Diaz-Kommonen®, H.Haggrén®
“Institute of Photogrammetry and Remote Sensing, Helsinki University of Technology, P.o.Box 1200,
FIN-02015 HUT, Finland - milka.nuikka@hut.fi, henrik.haggren(@hut.fi
Media Lab, University of Art and Design, Hámeentie 135 C 00560 Helsinki, Finland - lily.diaz@uiah.fi
Commission V, WG V/4
KEY WORDS: Photogrammetry, Cultural Heritage, Modeling, DEM/DTM, Photo-realism
ABSTRACT:
The aim of our research is to develop a method for producing 3D high-resolution photogrammetric reproductions of historical maps.
As an example we have created a reproduction of the Map of Mexico from year 1550. It is one of the oldest extant maps of the city
of Tenochtitlan, the ancient capital of the Aztec Empire, which was located on the site of present day Mexico City. The size of the
map is 114 cm x 78 cm and it is painted on parchment, which during the years has deformed and acquired a three dimensional
topography. Researchers are interested in the map because of the legends they could interpret from its texts and detailed pictures.
The map is however out of reach in a closed glass cabinet in the University of Uppsala, Sweden.
The requirements for the reproduction were that the three dimensional surface of the map is taken into account and the resolution of
the texture should be so high that also the smallest details of the map are distinguished. We created the reproduction using similar
photogrammetric techniques as in terrain mapping, though the used camera and implementation of the measurement coordinate
system were different than in traditional terrestrial projects. The most important advantage of the photogrammetric approach is the
possibility to create accurate reproductions, which can be examined with high magnification.
1. INTRODUCTION
Printed and material facsimiles of historical and archival
artifacts are frequently used by scholars for research, as valid
replacement for working with the original. For reasons of
security and preservation, facsimiles are also routinely used in
exhibitions by museums and libraries. Because of their value
and rarity, printed facsimiles are usually also exhibited in glass
containers, where they are out of the reach of the public unable
to peruse its contents. In contrast, researchers and audiences
frequently raise questions about both the accuracy and
consistency of digital artifacts, with regards to their material
counterparts.
In spite of the fact that digitalization could solve many
problems regarding access to rare and unique archival materials,
traditional image scanning techniques do not properly address
many of the needs and issues of museums and libraries that also
happen to be major research centers. For one, these methods
cannot accurately transfer radiometric and volumetric properties
of archival items made of organic materials, such as parchment
and vellum (Brown, 1994) and which through the passage of
time have acquired an almost three dimensional topography. A
sizable amount of archival artifacts in European libraries belong
to this category of parchment items.
As used in this project, the concept denotes a digital
representation of the original object of such a high quality, in
terms of resolution, color and shape accuracy, that it is accepted
by researchers who would normally require to get access to the
material version of the object. This is a significant feature that
distinguishes the proposed solution from other "postcard" or
"videogame? quality solutions, which are mainly intended for
non-expert audiences and experiential purposes. This latter
option makes it possible to develop diverse types of digital
cultural heritage artifacts targeted to different audiences. The
intensive data acquisition strategy presupposed for such a
product could also ensure that there will be enough for future
generation products.
Digital facsimiles offer significant benefits: They can protect
the original from excessive use, make the material available in
the best possible quality to the widest audience and provide the
option of reconfiguration and augmentation. The facsimile can
be made a part of new works.
In this paper we describe a process of creating a digital
reproduction of the Map of Mexico from year 1550. The project
is led by Dr. Lily Díaz-Kommonen from the University of Art
and Design Helsinki, Media Lab. Other collaborators are the
Helsinki ^ University of Technology, Institute of
Photogrammetry and Remote Sensing and the University of
Uppsala’s Carolina Rediviva Library.
At the Helsinki University of Technology we have been
developing a method for producing 3D high-resolution
photogrammetric reproductions of historical maps. The most
important advantage of the photogrammetric approach is the
possibility to create accurate reproductions, which can be
examined with high magnification. The reproduction of the
Map of Mexico was created using similar photogrammetric
techniques as in terrain mapping. Because the used camera and
implementation of the measurement coordinate system were
different than in traditional terrestrial projects it was interesting
to see how these techniques work.
