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CONCLUSION 
Data gathering is the most time consuming phase in building any GIS 
Because it is the most time consuming, it is imperative that the data 
be gathered to a set of requirements. This set of requirements is dif 
ficult to determine because many times data base requirements are to 
satisfy what appears to be short-term needs usually of large areas, at 
low accuracy requirements, MACRO data. Soon it becomes obvious that 
better data is needed, MICRO requirements. It is more economical to do 
the data gathering only one time to satisfy needs that are bound to 
"crop up" in the future. 
Existing maps, generally, will not provide data at the accuracy level 
needed for MICRO bases. 
Photogrammetric techniques are the only effective data source to 
satisfy MICRO data requirements. Normal photogrammetric instrumen 
tation makes data gathering expensive. It is only with the analytical 
stereoplotter system that this data can be gathered at a reasonable 
cost. 
REFERENCES 
Howell, Tommie F., Automation - The Key to Geographic Data Base 
Applications for Transportation: Workshop For Automated Cartography of 
Highways and Transport Systems, American Society of Photogrammetry. 
Chamard, R. R., Analytical Plotter for Data Input into Geo-Based 
Information System: Proceeding Volume 278, Electro-Optical 
Instrumentation for Resources Evaluation, The International Society for 
Optical Engineering. 
Rywell, Ross D., Niedzmiadek, H.A.: The Wetlands Analytical Mapping 
System - WAMS: Proceedings Analytical Plotter Symposium and Workshop 
1980, American Society of Photogrammetry