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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