on actual photography. For each of the 21 cases listed in Table 
IV, two independent values (using two operators) were determined 
for each of m. and m. No significant change in the experi- 
mentally determined valeues for m and m, was evident and, 
therefore the following values were adopted for all the cases 
investigated: 
2.04 (m, = 7.0"), and 
2. (n, 78.3). 
3.7. 1967 Series of Experiments 
  
A test area was established on one of the plastered 
brick walls of one of the photogrammetry labs. An area of 
2 x 2 meters was covered by two types of targets: Crosses 
and circular targets (Fig. 25). A cross and a circular target 
were placed side by side in 32 different locations throughout 
the test area. The spatial relative position of the various 
points were determined on the basis of a trilateration (on the 
face of the wall) combined with a triangulation (using three 
theodolites to intersect each target simultaneously). An ar- 
bitrary coordinate system was chosen and the X,Y, Z coordinates 
of every target were then determined. Our ZEISS SMK-40 was used 
for data acquisition. Normal cases with base length other than 
40 cm, as well as the convergent and tilted cases were simulated 
using only one of the SMK chambers at a time (Fig. 26). The 
distance and angles in Table IV were reconstructed. For each 
case five (5) independent stereo coverages were obtained. 
The investigation was planned to be performed in the 
following phases: 
a. Precision of determining X, Y, Z object coordinates 
of the cross targets. 
Precision of distance determination between cross targets.