X 
2 Parallax in aerial photographs. 
See fig. 1 
Known: H, s, R 
Unknown: dr 
Auxiliary quantity: dH 
| S2 + 
(R + dH) 2 - 
: R2 
(4) 
dr 
3 
1— dH 
" H — 
- dH 
(5) 
(s2 + ; 
2 RdH = 
= 0 
(4) 
1 s 
H 
1 dr 
" dH 
+ 1 
(5) 
S2 
dH = 
“ 2R 
(4) 
s 2RH 
2RH + S 2 
dr 
S2 + 
1 = 
S 2 
(6) 
S3 
dr = 
2RH + 
S 2 
(6) 
We introduce the following notation: 
dr v the distortion of the left-hand picture 
(dr v ) H horizontal parallax of the distortion in the left-hand 
picture 
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