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data. The digitizing process is done by pointing the 
measuring marks on the analytical plotter at features and 
recording feature coordinates in a format suitable to 
directly input into the data base. Coordinates can be in 
"real world" coordinates and they do fit "on the ground". 
The host computer in the analytical stereoplotter system 
provides the converting methodology that is required. 
Edit - Data digitized either from maps or aerial imagery 
must be checked prior to final placement into a permanent 
file in the GIS. This edit process from maps or imagery 
can be accomplished in much the same way. Use of an 
interactive CRT can be made to display digitized data as 
it is being gathered. Many of these systems can enlarge 
the data to check that lines properly join, etc. The 
operator can interact with the CRT to join lines, delete 
data, etc. Data should be edited layer by layer and with 
all layers shown to assure that, for instance, drainages 
and contours cross with proper relationships. After edit 
of data, it is placed in permanent files, as appropriate, 
for a particular GIS. 
DATA ACQUISITION COSTS 
Costs displayed in this section are those incurred by use of an analy 
tical plotter, specifically the US-2. Costs are related to a MICRO GIS 
need that is equal to a map at a scale of 1:4800 with a contour inter 
val of 10 feet and spot elevation accuracies of 2 feet. 
Cost of operation of the analytical stereoplotter: 
Cost of US-2 ~ $125,000 
Hourly Cost Amortization 
Amortization over a 5-year period 
or 5 years X 1,800 hr. yr. = 9,000 hrs. 
or $125,000 
9,000 hrs. = $13.89 hr. 
Total Cost per Hour to Operate Analytical Plotter 
Amortization US-2 
$13. 
.89 
Operator 
10, 
.00 
Related Personnel Cost 
1. 
.80 
Material Cost 
2. 
.75 
Overhead 
8. 
.50 
Total Hourly Cost $36.94