5. THE ORIENTATION OF PHODOGRAPUS 
The orientation of the photograpns i i 
several steps. Starting points are g J 
and the control points being present in a cart 
coordinate system. The looal zero points X , 7 G 
according to typical features prespecified for the image 
material to be restituted (aerial photographs, terrestrial 
photonraphs, image format etc.). Within the scope of t 
interior orientation tne matrix Gy is calculated from fi- 
ducial mark measurements for the correction of image errors; 
this matrix Gy is used for calculating xj, 75, M; dg and 
the matrix K in (4.0) for all segments. 
Subsequent to this the determination of matrix À is performed 
within the scope of exterior orientation. The matrices Gr 
and A are again used for calculating xj, Ye» Je: 55 and the 
matrix X. In the case of aerial photographs Ug and Ugzg can 
on principle be taken into account for the influence of the 
earths curvature and refraction. 
If restitution is not to be made in the control point coordi- 
nate system x, y,2, then by measurements in tne model those 
quantities must now be determined which are characteristic 
of the relationships between the coordinate systems. In the 
example of Section 4.4.1 this is the angle œ , for the resti- 
tution in a cylinder coordinate system {Section 4.4.2.2.) it 
is X4, % and r. The segments in the coordinate system 
X, 7, Z have to be fixed by suitable prescriptions. From 
their zero points we now obtain the final transformation 
parameters. 
Thus, the adaption of the algorithm to different problems is 
accomplished by the calculation of the matrices Ug and Ugg 
for each segment and their multiplication by the matrix F-. 
G2 
x] 
t 
(9 
; tj 
roD 
® 
6. OUTLOOK 
In Sections 3 and 4 we explained the algorithm for an analytical 
plotter using central perspective images as an example. 
It is easy to see, that the subdivision of the model into seg- 
ments also provides the possibility of allocating other orien- 
tation elements to each segment. Thus, the restitution of 
visualised scanner recordings in which other data of exterior 
orientation apply to each image point or each image line ere 
in principle possible. ilathematically one may proceed so that 
the imaging equations (2.1) are extended by the variable 
orientation elements. The time dependence is represented as a 
function of the flight path in the coordinate system (x, y, z). 
Hence the changes of the orientation elements are likewise 
functions of x , y , z and of dx, dy, dz. The basic equations 
(3.8) and (4.3) then hold just as with orientation elements 
which are constant for one image. 
Tor the restitution of recordings taxen with opto-mechanical 
scanners, TV-systems or amateur cameras use is frequently made 
of polynomials of the 2nd or 3rd degrees, which is also 
possible with the described algorithm. In (2.2) the matrix & 
then contains the partial derivations o? these polynomials with 
respect. to x, y, Z2. 
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