2) 
3) 
R M 
Z 
I. 
R, [87 
R, | My 
= 0 
R, | Mg 
o! 0g A, 
he oase in 
Ry 
Ry | "v 
My 
  
Bs [Ys 
Rz | My 
the pano 
  
   
a) The coordinates of the ground points are given in Gaussian coordinates 
N, E. It is a task of the program to trasform these coordinates into the 
more cohvenient rectangular system, ° 
b) The program can process equations the 
to given directions, 
c) The coordinates x*, y* 
‚t refer to ground points as well as 
are corrected before oomputing the internal tan 
gents, for the distorsion of the lens and for the effect of the atmosphe 
ric refraction, 
d) To the 12 unknowns x(°), y(°), 4(°) wg Ss P 
 Q) , À, B, C, is 
associated a matrix K =|K 
i KoK3K4KsK gk KgKoK4 o4 £12 | where each Ki can 
assume the value 1 or 0. In correspondence with the values Ki = 0, the 
program excludes the computation of the corresponding unknows. 
e) Àn unknown, or a group of unknowns, oan be introduced, as a known para 
meter, in the computation, and the program will compute the remainders, 
taking into oonsideration the given values, 
f) Áfter performing the computation of the unknowns, the program computes 
and prints out the discrepancies with reference to the points on which 
the orientation is made. The program may also compute the planimetric 
coordinates of any point when the plate coordinates x*, y* and the alti 
tude are given. j 
£) Besides the orientation parameters, the program computes and prints the 
following datas 
1) standard deviation of the unit weight, 
2) standard deviations of the unknowns, 
3) the variance-covariance matrix. 
3.5 - ACCURACY OF THE METHOD, 
First of all a careful study on the accuracy by which the unknowns of 
the space resection could be determined was carried out. It showed the 
following critical points: 
a) the parameters o and 9. that generally have a value of a few degrees, 
cause similar displacements of the point images on the film; 
b) the parameter 5 that generally has a value of a few degrees cause ima 
ge displacements on the film, that are negligible in comparison with 
those due to the other parameters. 
Owing to these considerations, the characteristics explained at point 
d) of the foregoing paragraph was introduced into the program. 
Real photograms being not available a theoretic model was analyticaly 
constructed, 
The determination of the photographic coordinates of a point, when 
the orientation parameters of a photogram and the ground coordinates are 
known is very easy in the case of a photogram taken under fixed conditions. 
It is instead somewhat complex, as we shall now show, in the case of a pho 
togram in movement during the shooting. 
In the case of the panoramic photogram, the problem consists in com 
puting the film coordinates x*, y* of a point, or else, which is the same, 
the internal direction tangents A e t , when the 12 orientation parameters 
and the ground coordinates of this point are known.