th 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
Grey value noise Flight path errors RES NM oe eh 
DTM 
2; [grey levels] 2, [m] 2; [mgrad] stand. dev. [m] mean [m] 
(1) 0.0 0.0 0.0 12 0.09 
(2) 3.0 0.0 0.0 1.50 0.10 
(3) 12.0 0.0 0.0 3.50 0.39 
(4) 0.0 0.4 0.08 2.51 0.15 
(5) 12.0 0.4 0.08 4.69 0.17 
(6) 0.0 1.0 0.2 6.89 0.81 
(7) 12.0 1.0 0.2 8.01 1.63 
(8) 0.0 2.0 0.4 19.86 2.33 
(9) 12.0 2.0 0.4 19.09 1.07 
  
  
  
  
  
Table 4.2: Numerical results of simulation 
5. FUTURE ASPECTS 
There exist various possible extensions of our approach. 
The introduction of a non-regular grid DTM adapted 
according to the roughness of the terrain, and the consi- 
deration of breaklines and discontinuities within the 
DTM can be achieved by altering the geometric object 
model. The simultaneous extraction of breaklines and 
discontinuities is more complicated to realize. 
A special feature of 3-line cameras is a different resolu- 
tions in each channel. For instance the MOMS camera 
has a resolution of 4.5 m for the nadir, 13.5 m for the 
other stereo channels. The matching process can be 
adapted to different resolutions. It should yield signifi- 
cantly better results than those obtained from the coar- 
ser level only. 
The simultaneous estimation of the parameters of exte- 
rior orientationin the least squares adjustment is already 
incorporated in the presented approach. As shown abo- 
ve this it is necessary for any practical application. Such 
investigations have still to be carried out. 
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