ments could be done either stereoscopically or monocularly. 
There is a number of stereocomparators and monocomparators 
currently commercially available. 
In the reduction of data in the analytic approach, the 
basic formulation derived for aerial photography could be 
utilized. Basically such a reduction involves the following 
phases (Moellman and Karara, 1967): 
a) Image coordinate refinement 
b) Formation of the stereomodel 
C) Absolute orientation 
d) Adjustment of coordinates 
e) Precision and accuracy of parameters and coordinates. 
2.2.3. Comments on the Analogue and Analytica! Approaches 
  
A. The choice between one approach and another is often 
influenced by the nature of the problem. For example, if the 
measurements needed refer to areas rather than discrete points, 
then consideration should be given to the analogue approach. 
B. The most important advantages of the analytic approach 
over the analogue approach is increased accuracy of measurement 
and increased flexibility of the procedure. According to Wasil 
(Wasil et al, 1965), the accuracy of the analytical approach in 
stereometric systems is estimated to be about five (5) times 
better than that of the analogue approach. Furthermore, with 
an anlytical method of solution it is generally possible to 
incorporate redundant data and apply an adjustment by least 
squares with its obvious advantageous features of checking 
blunders, and weighting of observations.