Leica GPS1200 Series Technical Reference Manual page 924

Determine Coordinate System - General
Transformation Characteristic
Advantage
Disadvantage
GPS1200
Description
• Errors in height do not propagate into errors in
position since the height and position transforma-
tions are separated.
• If local heights have low accuracy or do not exist,
a transformation of position can still be calculated
and vice versa.
• The height points and position points do not have
to be the same points.
• No parameters of the local ellipsoid and map
projection is required.
• Parameters may be computed with a minimum of
points. Care should be taken when computing
parameters using just one or two local points as
the parameters calculated are valid in the vicinity
of the points used for the transformation.
• Restriction in the area over which the transforma-
tion can be applied. This is mainly due to the fact
that there is no provision for scale factor in the
projection.
• The accuracy in height depends on the undula-
tion of the geoid. The bigger the geoid variations
the less accurate the results are.
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