of the camera during the soanning of the photogram. 
In this equation, the 12 unknown parameters are present and the measu 
rements accomplished are present in the terms t * t . 
L [ de dil eyoz £2 nollógà 
et us establish, however, that an equatio f this type homogéneous 
in the three linear parameters 
(n) 5 lon BY DS AP) im) ae 
Cb - 03 zy Yay Ui) 7 0)? 8 
We can therefore obtain the values of the relations between them, and 
not their values. In other words, if a system of equations of this type 
were utilized for ths relative orientation of the two beams, we would obtain 
only a relative orientation of the angular type, i.e., we would only know 
the directions of the two oriented beams and the direction of the conjunc 
tion of the photographing points. In order to give a definite scale to the 
model we have to introduce an equation into the system which is not homoge 
neous in the three parameters 8). For this purpose, the altitude Z of a 
point of terrain being established (it may be arbitrary, however), we can 
use relation e): 
(p) (p) (p) (p) 
LUN) A zu 9) 
x1) e V x(2) (1) X 
sis that the 6 parameters of orientation of the first beam (X 
z(0), Y (QUO ) and the altitude Z_ of the point on the ground are 
a datretily os 1dp1iShda, and the values of SET (4 ; Sym(4 (901) Át 43 
Bel e being known, it is desired to obtain the 12 Cn EET parameters 
which ario the orientation of the second beams, The 11 equations of the 
type 7) are written for 11 pairs of homologous radii and one equation of 
the type 9) is written for one pre-established pair ofhomologous radii. 
Through the difficulty inherent in the accomplishment of the computa 
tion (we are dealing with a system of transcendental equations), the pro 
blem of relative orientation is thus resolved in so far as, the values of 
the coordinates and of the tangents of direction satisfying the 1? equatims 
being known, it is possible by means of 5), 5’); 6), 6') to compute the coor 
dinates of the points of intersection of the homologous radii. These, toge 
ther with the coordinates of the photographing points, can then be subjected 
to transformation, The terrain coordinates will be thus defined for all 
3 H 
We designate this equation the "scaling equation", a (1) v m 
Y 
1 1 
points. 
Of course, in the computation stage, redundant equations will be uti 
lized and the method of least squares will be used. 
  
  
  
  
   
    
   
   
  
  
   
       
    
  
  
  
  
  
  
  
  
  
  
  
  
   
   
grai 
2) 
cb D c L3. .. d - kh 
LE 
i 
the 
The 
be 8 
8800] 
righ 
the : 
poss: 
ble : 
togr: