m É — model formation 
  
  
: — strip formation 
yet — Strip and block adjustment 
The information stored in the photographs constitutes the principal data input 
for the triangulation process. This information is influenced by various 
Terie parameters such as photo scale, type of camera used, type and stability of 
Ae image carrier, etc. Parameters influencing the triangulation process itself 
are: 
| 
ected model formation : 
ably be type, number and distribution of orientation points 
ations. preparation and measuring procedure adopted 
sed. mathematical model adopted for model formation 
instrument used, etc. 
ons 
omputer strip formation : 
© e type, number and distribution of wing points 
à mathematical model adopted for strip formation 
dels model errors due to relative orientation 
instrument used, etc, 
sults 
ly ad justment : 
o— type, number, distribution and accuracy of control points 
mathematical models adopted in adjustments, etc. 
Some of these influencing factors may be sources of information loss. 
For instance, the application of an unsuitable adjustment method may result 
in available information remaining unexploited. Other factors may be associated 
with the addition of irrelevant information or noise, as is the case with 
measuring errors added to the results of the strip formation. 
This addition of noise or the fact that relevant information may remain 
unexploited can occur at each stage of the whole process and thus contribute 
to reduce the accuracy of the final result as is illustrated in fig. 2. 
1, 
ints 
ied