SOME ASPECTS OF ON-LINE COMPUTATIONAL PHOTOGRAMMETRY 
by E.M. Mikhail and R.J. Helmering 
I. INTRODUCTION 
Analytical aerotriangulation techniques have become well 
established in present day production mapping operations. The 
primary objective of the triangulation procedure in map production 
is to provide supplemental control or exterior orientation parameters 
for the subsequent map compilation work with conventional or automated 
plotting equipment. Considerable research has been undertaken in 
order to automate the compilation process. Advances in electronic 
image correlation devices and digital computers have been applied 
to conventional plotting equipment, computer controlled plotters, 
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and completely digital map compilation systems ) in an effort to 
reduce the time consuming tasks associated with the compilation of 
maps. Although the operation of advanced automated map compilation 
systems depends on parameters derived from analytical solutions, 
suitable research has not been devoted to the problem of automating 
the analytical triangulation process. 
In aerolriangulation, a mathematica] model is derived which 
represents the physical conditions encountered in a strip or block 
of photographs. The object space coordinates are related mathematically 
to the image space coordinates through the elements of exterior and 
interior orientation. The operational procedure for analytical