THE USE OF NON-METRIC CAMERAS 99
Fıc. 4. An oblique photograph of the
accident scene showing the local net
used to determine reference points for
the determination of interior and exterior |
orientations. The camera taking the > |
movie was located in the vicinity of the Mio
station in the foreground. CE TI SPAN 34-470 us
x.
I wt
À 4i
i 1
RACK 8-11:0 +}
DHC - CHIPMUNK ---ON WHEELS
Fic. 5. The coordinates of all points indi-
cated by arrows were scaled off these draw-
ings of the aircraft.
— dii di; dis
=9 2
dy, dy, dys Zz
N| =|
Use of the scale factor S and the matrix D now permitted the determination of the correct
location and orientation of the airplane for each single frame.
The results obtained from each seventh frame ofthe last 154 frames prior to impact, and the
aircraft orientation and position at impact ofthe filmed sequence, are given in Figure 6 which
shows in addition to a three-dimensional presentation, three two-dimensional projections.
The results were forwarded to the agency investigating this fatal accident and served as
primary evidence in a damage suit brought by the late pilot's widow.
The general aircraft position was determined with m, — m, = + 1.0mand m, = + 8.5m. The
distances y which were derived by means of the scale factor S were smoothed out prior to
producing Figure 5 while all other values were used as derived from the computations.
Determination of three-dimensional information using a beam splitter attachment. A
system which can be used to obtain three-dimensional information from a single photographic
exposure is the beam splitter attachment, shown in Figure 7.
It consists of two surface-coated plane mirrors and a surface-coated 90? prism. When
mounted in front of the camera lens, two separate bundles of rays are formed so that a
photographed object is recorded in two different locations on the photograph. This photo-
graph contains, therefore, the same information as offered by two photographs taken by
simultaneously operated, perfectly synchronized cameras, which is of particular interest in
photogrammetric studies of high speed processes. The base length of the stereo photographs,
