OF AERIAL PHOTOGRAPHY 
   
   
  
   
   
    
  
  
  
   
   
     
    
     
    
   
   
   
   
    
    
   
  
COMPUTER-AIDED INTERPRETATION 
of USING THE STEREOCORD G 2 
dular | 
eT H.Mohl, Fachhochschule für Technik, Stuttgart | 
V H.W.Faust, Carl Zeiss, Oberkochen 
apable 
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data 
Abstract 
Stereoscopic interpretation of aerial photography is the classic 
method of remote sensing. In practical remote sensing this is 
still one of the most important methods. From the stereoscopic 
model the expert can recognize and measure geological,  hydro- 
logical, agricultural, arboricultural, and urban constructional 
details. 
For a long time the parallax bar was the interpreter's tool 
for measurements. Today with the electronic desk calculators 
more accurate and more intense investigations are possible and 
magnitudes such as height differences, distances, slope and 
azimuth angles, planimetric and surface areas, and volumes can 
be measured on-line. 
The STEREOCORD G 2 of Carl Zeiss, Oberkochen, is exemplary for 
a combination of a mirror stereoscope and a desk calculator. 
The aerial photographs are mounted on a photo carriage, the 
position of which is continuously controlled by encoders. From 
the photo coordinates the calculator computes the terrain co- 
ordinates. The orientation of the photographs on the photo carriage 
is simple. Tip and tilt of the photographs are determined from 
the photo coordinates of some control points, and then auto- 
matically taken into account for the coordinate transformation. 
An important part of the system is the software for computing 
the orientation, the coordinate transformation, distances, 
angles, areas, and volumes. The first STEREOCORD software made 
approximate allowance for tip and tilt. Now new software has 
been developed which has considerably improved the system's 
accuracy.