INSTRUMENTATION FOR A CADASTRAL LAND INFORMATION SYSTEM 
Marius C. van Wijk 
Photogrammetric Research 
National Research Council of Canada 
Ottawa, Ontario, KiA OR6 : 
Commission II 
ABSTRACT 
The requirements for photogrammetric instrumentation, to be used for data 
acquisition in a computerized cadastral land information system, are 
discussed. A prototype system has been installed in Colombia as part of 
experimental project, carried out jointly by the National Research Counci 
Canada and the Instituto Geografico "Agustin Codazzi" of Colombia. The 
system configuration is described and test results obtained with the ster 
orthophoto components are presented. 
INTRODUCTION 
The selection of photogrammetric data acquisition equipment for a compute 
land information system depends on a variety of factors. The accuracy 
required for the information is a primary consideration and is affected t 
great extent by the value and the use of the land. Different accuracy 
specifications are usually set for urban and for rural areas, which may r 
in a requirement for different types of photogrammetric equipment.  Relat 
this is the question, particularly for rural areas, whether the parcel- 
boundaries to be digitized, are targeted prior to the aerial photography 
whether their identification in the images is based on natural features s 
as road and vegetation patterns. In the latter case there may not be a 
justification to use high precision - usually meaning sophisticated and 
expensive - equipment. 
A consideration which also may influence the selection of equipment is a 
possible decentralization of data acquisition procedures. The collection 
field information is.often organized at a regional level and there may be 
certain advantages of performing the actual digitizing of this informatio 
the regional cadastral offices as well. In this case it may be considere 
have the digitizing and the field work carried out on a rotational basis 
the same persons. These may not be highly trained photogrammetric operat 
so that relatively simple photogrammetric digitizing equipment would be 
advantageous. 
Other factors which have to be taken into account in selecting the equipm 
are the possibility for verifying the completeness, checking and, if 
necessary, editing of the data bank information. Last but not least the 
is an important factor, particularly when considering that, once the 
information has been collected and digitized, the equipment will be mainl 
used for updating the land information, which may not require its use on 
full-time basis and therefore may not justify the purchase of sophisticat 
and expensive instrumentation. 
THE PILOT PROJECT "CADASTRE LATIN-AMERICA" 
The pilot project "Cadastre Latin-America” is the result of the interest 
Latin-American countries, and Colombia in particular, to develop an integ 
multipurpose land information system and to upgrade the existing cadastra 
systems which are of limited capability and which were originally establi 
mainly for taxation purposes (Gonzalez-Fletcher, 1980). The project is 
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