production, satisfying only the need for metric accuracy, while larger 
scale photography is' used to'supply the required semantic information. 
In this way the otherwise high costs of thé photogrammetric operations 
for a large number of large scale photographs are significantly reduced. 
As a result of the foregoing analysis we can now introduce the concept of 
different principal project structures from which the planner has to make 
his choice. 
2.3. Process components and sub-processes 
- 
Next we have to realize that the development of photogrammetric technology 
has provided us with a large choice of means, by which each of the different 
functional phases of the total process can be executed. 
These means, consisting of many different items of equipment and methods can 
furthermore be combined in many different ways. 
For any such feasible combination of equipment and method we will coin the 
concept of process-component. These are ihe smallest units available io ihe 
  
planner to design and compose & complete mapping process. 
It becomes quite VON that it would be virtually impossible to compile a 
complete list of all process components which are either used or feasible, if 
One only considers all possible combinations between stereo-plotting equipment 
and plotting methods. 
A further useful concept might be that of sub-processes , consisting of a number 
of specific process-components which are used: for the execution of an indivi- 
dual functional phase (e.g. aerial triangulation) or even combinations of such 
functional phases. 
In order to define process-components, the concept of process-parameters will 
be used. In most cases, these process-parameters will have a qualitative 
meaning (such as type of equipment, or method) but they might also assume a 
quantitative character (such as photo scale, forward and side overlap, bridging 
distance etc.). 
Accepting these concepts, the task of the planner of designing a photogrammetric 
procedure can now be defined as the task of determining the process-parameters. 
A tentative list of the different process-parameters, meant to describe a 
complete photogrammetric procedure, has been compiled in table 2.. 
Film-fil 
Photosca 
Flightpl 
Processi 
Auxiliar 
Processi 
Preparat 
Executic 
Ad justme 
Photo-ir 
Preparai 
Executi: 
Field i 
Field c: 
Numeric: 
Cartogr: 
Reprodu: 
  
2 A. Per 
The choice 
objectives 
a) The 
b) The 
With respe 
the perfor 
reliabilit 
With respe 
be incurre