Technical Data
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Reduction to
mean sea level
D
2
The values for
D
2
are always negative and are derived from the following
formula:
Projection distor-
tion
D
3
The magnitude of the projection distortion is in accordance with the projection
system used in a particular country, for which official tables are generally avail-
able. The following formula is valid for cylindrical projections such as that of
Gauss-Krüger:
In countries where the scale factor is not unity, this formula cannot be directly
applied.
D
2
Reduction to mean sea level [ppm]
H
Height of EDM above sea level [m]
R
6.378 * 10
6
m
TS_106
Δ
D
2
= -
H
R
· 10
6
D
3
Projection distortion [ppm]
X
Easting, distance from projection zero line
with the scale factor 1 [km]
R
6.378 * 10
6
m
TS_107
Δ
D
3
=
X
2
2R
2
· 10
6
