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and feasibility studies in cartographic, photogrammetric 
and engineering disciplines. 
The area of study was into the urban area of the City of 
Manizales (Colombia). 
Equipment: 
- Sheets at 1:2.000 scale, issued 1989. 
- Aerial photographs, 1:8.000 scale, issued 1993. 
Software: 
-Infocam/ Oracle 
Hardware: 
- Workstation 4000-VLC 
- Workstation Vax 4000-90 
- Analytical plotter DSR15 
- Digitizer Calcomp 9500 
- Drum Plotter Calcomp Classic 4036 
3. PROCEDURE 
- Select and analyze the capturing source, for example: 
photos, cartographic information and reports. 
- Capture of contour lines by manual digitizing using the 
Collector module of Infocam. 
- Capture of contour lines by conventional photogrametric 
processes using the Collector module of Infocam. 
- Capture of contour lines from a grid of points and 
breaklines using the Kern and Dtmcoll module of Infocam. 
- Subsequently, using the Image and Scop modules of 
Infocam, the data were edited and processed. 
- Obtention and output of products: plotter, printer, report 
and display in screen. 
- Verification of quality and accuracy of products. 
- Adjustment and final corrections. 
- Output of the final products. 
4. RESULTS AND CONCLUSIONS 
It is very important for the final product the quality and the 
accuracy both of the data source and the capture 
methods. 
The capture of data for photogrammetric methods offers 
the best results than the other methods. 
The generation of the DTMs allows to show the main 
details and relief forms that are not visible with other 
kind of methods. 
Grid models have the advantage of a regular structure of 
the data, wich simplifies the use of the DTM. 
High fidelity and easy to use DTMs have the potential to 
replace the existing graphical contour maps and to 
describe all relevant topographical height information in 
digital form. 
Finally, the diverse products obtained by DTM are very 
important in the analysis. They may be used in different 
studies as: 
- Construction of highways. 
- Filling and cutting operations. 
- Environmental assessment. 
- Soil studies and land suitability. 
- Infrastructure for telecomunications. 
- Geographic studies. 
- Design of utilities. 
In the same way, the DTMs are more easy to update 
than other kind of elevation data. 
5. REFERENCES 
Ebner, h. and Fritsch, D., (1986), 
High Fidelity Digital Elevation Models 
Elements of Land Information Systems. 
FIG Congress, Toronto. 
Kennie J., and Mclaren R., (1988), Modelling For Digital 
Terrain 
and Landscape Visualisation, Fotogrammetric Record. 
Leica, (1990), Scop To Create and Apply Digital 
Elevation ; 
Models, User Manual, Institute Photogrammetrie, 
Stuttgart, Germany. 
Makarovic And Charif, (1988), Digital Terrain Models, 
ITC, Holanda. 
Stefanovic P., Radwan M.,and Tempfli K., (1989), Digital 
Terrain Models:Data Adquisition, Processing and 
Aplications. 
International Archives of Photogrammetry and Remote Sensing. Vol. XXXI, Part B4. Vienna 1996