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MICRO GIS must be structured through the use of more accurate data 
input and are usually used to develop "action plans". This data is 
often gathered for smaller geographic areas. Users of this type of 
data are utility companies, intensive land management groups, engin 
eering designers and construction organizations. These GIS's consist 
of data that is provided by using accurate large-scale maps and 
appropriate scale aerial photography. Output from these systems are 
usually large-scale strip maps, utility facility placement maps, earth 
work volumes, etc. Examples of these systems are the Texas Department 
of Highways and Public Transportation's Highway Design Systems and 
Southwestern Bell Telephone Company's Automated Mapping and Facility 
Management project. 
THE ANALYTICAL PLOTTER IN THE MICRO GEOGRAPHIC DATA BASE STRATEGY 
The analytical stereoplotter can be used in the data gathering phase of 
MACRO systems, but it is not usually used because the data does not 
need to be accurate and can be gathered more economically by utilizing 
data that may already be in a computer compatible form. In MICRO 
systems the analytical plotter is the most economical system to use as 
a gatherer. The analytical plotter can provide data that is accurate 
and designed to fit the MICRO need. The broad steps In gathering these 
data are: 
o Determining Needs - The data base requirements are stringently 
determined to satisfy the final use. These requirements will 
determine the scale, elevation accuracies, and other special 
needs such as the digitizing of light and power poles, manhole 
covers, etc. 
o Planning to Meet Needs - This step involves research of 
available material such as maps to determine accuracy, content, 
etc., available aerial photography, and control. After this 
research, required planning is done to acquire aerial photog 
raphy and field control to fill the gaps in the existing 
information. 
o Acquisition of Needed Data - Existing, useable maps, and other 
information is purchased in a stable base-scaled media. Aerial 
photography is flown and field control is performed. All 
materials are inspected and properly ordered for use. 
o Digitizing - Coding of data needed is designed to fit the GIS 
and CAC to be utilized. This will set special requirements on 
how the data is to be digitized - by layers, point features, 
etc. This menu of codes for various features digitizing will 
be the stereoplotter-digitizer operator's bible. 
From Maps - Digitizing from maps will be done on a table 
capable of sensing positions by use of an electronically 
sensitized surface. Features will be traced and in the 
process, the features will be converted to data in 
necessary format. 
From Aerial Photography - This is the digitizing process 
that makes the analytical stereoplotter so powerful. 
Digitizing from aerial photography that is properly 
controlled also provides the most accurate and uniform