DETERMINATION OF APPROXIMATE VALUES FOR BUNDLE ADJUSTMENT *) 
Kurt Novak 
Vienna Technical University 
Vienna, Austria 
ABSTRACT 
Bundle adjustment algorithms need both approximate values and control 
points to calculate the orientation of photographs. This paper 
presents methods how to derive the parameters of the interior and 
exterior orientations from image coordinates only. Geometrical 
relations at the object are used instead of control points. 
Goedetical determination of control points is not necessary. An 
example shows the practical use of these approaches and compares the 
results with bundle adjustment. 
1 INTRODUCTION 
In terrestrial photogrammetry, non-metric cameras are frequently used 
as they are easier to handle and not as heavy as metric cameras. 
Generally the position of the projection center and the tilt angles of 
the image plane as well as the principal distance and principal point 
of a photograph are calculated by bundle adjustment. Control points 
measured by goedetical means and approximate values of all parameters 
are necessary. These approximate values are either roughly estimated 
or geodetically determined. 
The approaches described in this paper derive the orientation 
parameters directly from the image coordinates without exterior 
information but the object form. For calculating the exterior 
orientation of two photographs, a plane object is necessary /2//7/. 
If three photographs are available, the principal distance can be 
found additionally. To get the complete interior orientation from one 
or more images, orthogonal directions at the object are used /1//6/. 
The lens distortion may be neglected as a distortion polynom can be 
defined in a following bundle adjustment. 
*) This paper is part of a thesis to gain the title Doctor of 
technical sciences at the Technical University of Vienna /5/. 
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TC ES