Table 4. 
  
  
  
  
  
Unit — millimetre 
Test i 1 2 TR 3 Fi 4 Number 
; A ; of points 
Object HRS AU 
Well defined objects 
Corners of houses ...... 36 51 3 59 27 50 33 33 48 
Poles | Joma Satins 17 4300 2677 38 :1:29.20 ..32 32. 7 
Wells 1... 509 0h 2 26 18 20 16 17 11 21 18: 10 
Kerbstones :...........…. 39 21 1 48 71 56 109 54 4 
Railways seio nn 32 18 25 21 22 17 24 26 8 
Walls er 52 57% 29 5 8.12 14 50 4 
Root mean square ........ 35 26 35" 36 #35 33 159 38 8] 
Diffuse objects 
Beads ........... 66 83 97 190 44 69 59 176 24 
Hedges at es . 129 100 3196 119 333 84 136 144 7 
Fences 5. savin 2 949 591 522^ 71 199 90 40 36 13 
Root mean square ........ 87-88 127 136 222 ^81 89 133 44 
  
The values in Table 4 were procured in the following manner: 
For point-shaped objects the average of the coordinates of the four 
cases has been calculated. Regarding the individual mappings, the devia- 
tions from the averages have formed a new series of values with averages 
and standard deviations. 
For line-shaped objects, an average line has been adapted to the mea- 
surings of the four cases and the deviations at right angles to the average 
line have been indicated with averages and standard deviations. 
The averages are a measurement of the local constant changes ol 
situation while the standard deviations are local irregularities in the situa- 
tions. The size of averages and standard deviations have been estimated 
A A 
as root mean squares, indicated as m and s. 
The elevation plotting was studied on the one hand in the form of 
point measuring, on the other hand in the form of contouring. 
1. At 185 points determined geodetically as to position and elevation, 
stereo plotting was carried out. The root mean squares of the differences 
between terrestrial and stereo plotting is shown in Table 5. 
218