trast of the objects, can be predicted. The use of cameras with 
forward motion compensation will give better results of identi- 
fication. The sensitivity of the photographic materials can 
slow down, but the resolution will increase. Just for tasks in 
urban areas it will help to economize the signalisations. 
For the determination of details, superimposition of already 
measured and stored data into the optical path of an analytical 
plotter will help those who are working on it. (See fig.4) 
T ener : 
GRAPHIC OPTICAL 
DATA SUPERIMPOSITION 
  
STEREO MODEL 
  
COMPLETION 
LAND INFORMATION SYSTEM 
  
  
  
Figure 4: Optical superimposition of stored land related 
data into the stereomodel 
The superimposition should be reduced because of the image 
orientation and the terrain height and has to be updated on- 
line. There should be no influence on the measurements, what 
means that the superimposition has to disappear if needed. 
Superimposition will help to find and identify objects and 
to classify them. 
The data of a land information system are meaningful, if the 
variety of all data of the reality is not too much reduced. 
The model which is formed of the reality in a land information 
system should at least be able to meet all tasks which are 
given to it. The number and the kind of different classes 
has to be chosen in a task specific, system depending way. 
The identified data are classified with the help of predefined 
rules. The belonging to a class is added to the coordinates 
either by attributes, by the allocation into logical layers 
or by code numbers. 
All the predefined different classes cannot be identified du- 
ring the photogrammetric process of data collection. For ex- 
ample it is impossible to classify an identified manhole to the 
right class of sewage or rainwater as well as it is impossible 
to figure out whether a highway belongs to national or regional 
administrations. This is one request for the subsequent treat- 
ment of photogrammetric data. 
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