4.4 Image set-up 
  
(a) Single Image. 
In the image set-up module the relationship is established 
between the plate carrier coordinate system and image coordinates. 
If .fiducial marks or.a reseau are available, then thís will be 
used for a proper inner orientation. If no elements of the 
inner orientation are known then arbitrary reference points 
(at least two) need to be measured. Depending on the number 
of fiducial marks, grid or reference points three different 
transformations are possible: 
linear conformed (Helmert) 4 parameter, 
affine (6 parameter), 
bi-linear (8 parameter). 
Fiducial marks may be of two types: single points and 
crosses. For lens and film deformation a mathematical model is 
chosen as described by Karara (1979). 
(b).Stereo Model 
This is an application of the single image set-up routine 
to the left and right plate carrier (even with .different 
camera types). 
(c) Block 
This can be in the first instance a repeated application 
of (a). In excess of this however, one may 
- have several photographes on each plate carrier; this 
can be of interest with small format data. 
= have for each photograph.a different camera. 
4.5 Data collection and preliminary orientation 
  
(a) Single Image 
Here several cases have to be considered, including plane, 
and non-plane objects. 
* Plane object and unknown inner orientation: 
At least 4 points (defined in the plane) are necessary 
to solve the collinearity equations. This case is also 
known as the numerical rectification of a single photo- 
graph. 
* Plane object and known inner orientation: 
At.least 3 points must be available. A space resection. is 
used to determine approximate values for the exterior 
orientation. 
*  Non-plane object and unknown inner orientation: 
At least O0 points with their Xx, Y, Z coordinates are 
needed. Approximate values for inner and exterior 
orientation are calculated using the DLT-method. 
* 
Non-plane object and known inner orientation: 
At least 3 points with X, Y,.Z.coordinates must. be 
available: A space resection is used to determine 
approximate values for the exterior orientation. 
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