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INTRODUCTION
in this report, a review is given of the present state of
knowledge regarding systematic image errors and their effects
in aerial triangulation. It is wellknown that systematic
image errors which are an important component of the total
image error cannot be properly described by a theory of
independent random image errors. A separate theory is necessary
to study the effects of the systematic image errors. Based
on this theory, it could be demonstrated how dangerous and
unpredictable the effects of systematic image errors in
triangulation can be (section 3). The methods known to detect
and compensate for these effects after triangulation are
cumbersome and elaborate (section 4). It follows that in
practical triangulation projects great care should be taken
during flight mission, film processing and handling, in order
to keep systematic image errors within reasonable limits.
The definition of systematic image deformation is in itself
already a difficult task. An intuitive definition is given
in section 2 on which the two following sections are based.
The problem of definition is however taken up again in section
5, where an attempt is made to indicate a more complete
definition of not only the systematic image errors but of the
image errors as a whole,
A DEFINITION OF SYSTEMATIC IMAGE ERRORS
Let us for the time being use the following intuitive definition
of systematic image deformation:
Let us consider a photogrammetric block consisting of P
photograms.In every photogram nine points are selected at
standardized locations (cf. figure 1). We then define the
Systematic image deformation by the set of 2 x 9 coordinate
errors at each of these points, which is the same for all
P photograms in the block. We also agree on some (linear)
interpolation rule, by which the coordinate errors may be
obtained in any other point of the plates.