Because of the earth rotation effect the scanline direction 
of the MEOSS CCD linescan camera will not be vertical to 
the satellite ground track (x-direction of the PSOM image 
products) fig. 4. 
In spite of. tnis-yew tilt between camera and the x- and 
y-coordinates of the PSOM image products, these will show 
constant x-paralaxes and no y-paralaxes for the reason of 
directional coincidence of the satellite ground track and 
the stereo bases. 
Terrain Height Evaluation 
  
Since the MEOSS stereo triplets show (nearly) no y-paral- 
laxes, epipolar lines will be (nearly) parallel to the 
subsatellite track. Hence, image correlation for terrain 
height evaluation can be performed as a mainly onedimen- 
sional process. 
For reason of the split perspection the stereo triplets 
contain ne principal points, only a principal line coin- 
ciding with the Nadir track of. the satellite. Standard 
instruments for photogrammetric stereo evaluation correct 
automatically for central perspective effects in x- and 
y-direction. To make use of these instruments for eva- 
juation of-MEOSS stereo triplets this automatic correction 
must be suppressed or countercorrected for the x-direction. 
In analytical instruments this can be achieved by software 
changes. 
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