54 BALLISTIC PHOTOGRAMMETRY, DISCUSSION
known to be accurate to at least = 2 y.
It must be concluded therefore, that bias
errors exist which are covered up due to sym-
metrical nature of the distortion pattern. Thus,
a second type of evaluation was performed as
first evaluation. Figure 7 shows that the tan-
gential distortion over most of the lens cone is
within the — 2 micron limit of the measuring
accuracy. However, there are areas where
variations in tangential distortion up to 8
lt!
Fig. 5. Radial and Tangential Distortion. Astrotar BC-4. No. 265.
indicated in the lower right hand side of Figure
3. The corresponding result is graphically pre-
sented in Figures 5, 6, and 7. Figure 6 demon-
strates clearly that the radial distortion, in this
case, is expressed much better by an elliptical
pattern, as shown by the somewhat irregular
heavy lines in contrast to the thin lines repres-
enting the radial distortion obtained from the
microns occur between rather adjacent points.
Such local disturbances are objectionable espe-
cially if the photogrammetric method is used
to record a sequence of individual points as
eg a flashing satellite, thus depending entirely
on the possibility of reconstructing precisely,
for the purpose of triangulation, the spatial
configuration of individual rays.
Discussion
Herr Prof BURKHARDT: Ich danke Herrn Dr
Schmid fiir seinen sehr aufschlussreichen Vor-
trag. Ich glaube, es sind eine Menge von Pro-
blemen angeriihrt, die uns auch in unseren
anderen Arbeiten ausserordentlich interessie-
ren. Ich darf zunächst Herrn Rosenfield bitten,
die Dis
Ausseru
Schmid:
Mr (
to his p
Optical
Camera
Mr
about
that you
tenths
What i
standar
thinkin;
Mr
measur
error of