Since Meydenbauer came up with the idea to set up
archives for photogrammetric documentation, more
than 100 years ago, many thousands of buildings and
monuments have been photogrammetrically recorded.
But striking the balance after more than hundred years
of architectural photogrammetry, we must admit that
photogrammetry has failed. Or the responsible ones.
Who are the responsibles ones? In our opinion the archi-
tects. But we hear from them the contrary, of course.
In fact, we only have a few percent documented. And
we have nearly nothing done to collect photogrammet-
ric documents of the architecture in the so-called third
world. In many of the poor countries, people’s main
interest is concentrated on overcoming starvation, dis-
eases and unemployment, much more urgent problems.
We have to understand that architectural photo-
grammetry is simply of no importance to them.
Reading today’s newspapers it seems easy to me to
predict that things will not change basically in the near
future. But something must happen.
CULTURAL HERITAGE - CULTURAL CONVIRONMENT
- CULTURAL FUTURE
Presence is just a moment, we live between past and
future. Man is a distinguished creature with a free will,
created and destined to be responsible for the whole
natural convironment, where he lives together with
plants and animals, small and big. We ought to be
thankful for being allowed and privileged to live with
science and art, e.g. music and architecture, hence at
the same time we are responsible for the cultural con-
vironment. Our free will allows us to decide for noise or
music, for war or peace, for conservation of the cultural
heritage or for its destruction and decay. The more we
inherit from our ancestors, the richer our children will
be, rich not merely in the materialistic sense, but rich in
culture and heart.
No tree can exist without roots. Nor should our children
live without the cultural roots which nourish and stabi-
lize all of us. The inherited as well as today's great and
beautiful architecture - selected and evaluated, of
course - is and should remain an important part of our
cultural convironment. If we had the money spent for
bombs and arms, all our architecture could be great and
beautiful. The minimum we photogrammetrists can do,
is to help to collect metric knowledge and image-docu-
ments of any monument, which might be used to re-
store or rebuild it in case of damage or to remind others
of its excellence. Future generations shall know about
appearance, condition and artistic impression of today's
architecture in general and of every building in particu-
lar.
The question is what photogrammetry's contribution
should be to the preservation of the cultural heritage in
the future, especially what we can do in CIPA and
Commission V.
TASKS OF ARCHITECTURAL PHOTOGRAMMETRY
Task 1: Quick and worldwide photogrammetric docu-
mentation of the architectural heritage.
In order to accomplish such a big job within a reason-
able time of, say, 25 years i.e. within one generation,
fast and simple methods of documentation as well as
for restitution have to be used besides the professional
methods, (whose instruments are much too expensive).
That means we have to speed up the documentation of
architecture 250 times! In the majority of cases, the
inventory, historical analysis and restoration demand
such high accuracy as offered by professional photo-
grammetry (Almagro, 1991). Semi-metric or non-metric
cameras, reduced format plotters and/or digitizer tables,
personal computers and commercial drum plotters are
sufficient. Object control should be reduced to "simple
control” (Waldhäusl/Peipe, 1990). In many practical
cases, plotting is required of independent models, only.
With some additional, but simple control information,
bundle block adjustment yields reliable results. This
method is efficient, usable and cheap as far as collec-
tion of photography is concerned, but a bit more expen-
sive than professional terrestrial photogrammetry and a
bit less accurate as far as restitution and further data
processing are concerned.
World-wide there are many and highly intelligent people
producing and collecting excellent architectural photog-
raphy, capable to easily learn the but few and simple
rules to be applied for metric documentation. If the job
really has to be done within one generation's life time,
it is advisable to motivate them to help us. We have to
teach them some simple rules (Waldhäusl/Brunner,
1988), which we called the 3x3-rules. Three geometri-
cal, three photographic and three organizational rules
which are well known to any professional: How to
prepare control information, how to provide for multiple
coverage by all-around photography and how to get
stereo-partners for stereo restitution. The inner orienta-
tion has to be kept fixed, the illumination should be
homogenous, the camera should be stable and of the
largest available format. How to make proper sketches,
how to write the protocol and how to check up the
results finally. Each of these nine rules is explained in
detail.
CIPA should study, improve, approve and publish these
rules properly. Then these rules should be distributed
among interested groups. At the same time, a collection
of documentations has to be organized. Photo-
grammetrists and architects could gain a new field of
activity, i.e. to inspect, approve and collect these docu-
mentations and to manage an archiving system, com-
municating world-widely. Leaving the mass documenta-
tion to others, they could dedicate their efforts to the
surveying of the more complex and more difficult ob-
jects, like cathedrals and castles.
Besides non-metric and professional photographic cam-
eras, also (still-) video cameras are widely used, nowa-
days. The 3x3-rules should be extended also to these
videogrammetric cameras. We should try to get into
contact to one or another TV-station and to motivate
them to collect proper videos. The big advantage of
"amateur-documentation" is the fact that the many
expert tourists could collect many, many objects also
out of and for developing countries.
Task 2: The analytical methods of restitution should be
further developed and further propagated.
The simplifications of the very complex and universal
combined adjustment software systems are not yet
simple enough. Non-photogrammetrists run into difficul-
ties quite often. On the other hand, there are also many
photogrammetric experts who are not yet acquainted
with all the possibilities of combined bundle adjustment.
And many practising and photogrammetric institutes
have not even started to use bundle adjustment or non-
metric photography.
In Europe, more than ten university institutes have
started to compare their skills in the restitution of non-
metric photography using ORIENT (Kager, 1991). A test
object hs been selected, a small but beautiful building in
Vienna (Waldhäusl, 1991). The aim of this international
cooperation is to convince the users of architectural
photogrammetry that non-metric and semi-metric cam-
eras render sufficiently good results for many practical
purposes. Another goal is to provide all the members of
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