The striking superiority of the 120° over the 90° photographs in this respect can be seen from the 
comparison of the requiremens for block triangulation from photographs taken from the same flight 
height, for instance when the ceiling is limited (Fig. 23). 
  
  
  
  
  
  
  
  
  
  
  
  
X AA E gd 
: 7 
ep I fl LT ln 
| 
  
p AA : | | f-150mm 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
H= 5400 m 
Fig 23 The significant advantage of the super wide angle camera in block triangulation where the ceiling is limited : 
The number of models are in the ratio 9:25. 
Comparing a square block of 5 x 10 models of 90° photography with 4 x 8 models of 120° photography, 
one sees that the latter with 32 models and some 31 pass points covers 1.8 times the area of the 50 
models with about 37 pass points (Fig. 24). 
  
  
  
  
  
  
  
  
  
  
  
  
D——177—7F77 T= 1-1" Q T © T ——< I 
| | | | | 
| | | | | | | i 
$ | | | 
| | | | | | $ | 
Y T 1 = | 1 | i 
| | | | i 
| | | | i 
7 | | 
4 = | + | 
| | | 
—1—— | i 
or. I- —HL- -i —— 1 | | i 
: 
$ | 9 q | $ | 
1 | fl 
| | | 
1 
+ pu | | 
+ i 
B— —(— fctentieme use e | 
1 $ i 
I 
| | 3 | | | 
+ T T + | : 
i 
| | 
| Î 
e + e ————L— . — d a bL + + | 
f= 150 mm | 
ÿ 
{| 
4 — ————— - — 6 A i — 6 | 
I 
f= 90 mm | 
Fig. 24 Block triangulation with super wide photographs is easier than with wide angle photographs, due to both 
the number of models and the number of pass points necessary.