International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Volume XXXIX-B7, 2012 
XXII ISPRS Congress, 25 August — 01 September 2012, Melbourne, Australia 
     
In these first elaborations without the use of the GCP (Figure 8) 
but only with the satellite RPC, we see a systematic error in the 
positioning layout. (Table 1) 
In the second step we repeated operations using GCP by GPS 
survey, obtaining the results described in the following Table 2 
and in Figure 10. 
Table 1 Control points without GCP. 
  
  
  
   
    
    
  
  
«Top-most layer 
PUNTODT2 
Location: 600.741,352 4.463,013,671 
  
  
Field | 
Value 
  
  
   
    
   
FID 
Shape 
Layer 
X 
¥ 
z 
  
  
1 
Point 
PUNTOOT2 
600741,769 
4463014,112 
789,997 
  
  
  
  
   
      
   
  
   
   
  
Figure 9. Error in positioning of GCP (test 1) 
  
Figure 10. Control points in the second step on test 1 
  
  
X Z 
lkon 1 589150,935 4463237,198 725,024 
lkon 2 599297,519 4463199,118 704,934 
Ikon 3 599571,338 4463566,454 799,892 
Ikon 4 599349,550 4464724,453 564,610 
Ikon 5 600371,615 4462620,327 683,075 
lkon 6 600479,332 4462530,172 675,404 
lkon 7 599846,754 4461978,045 465,860 
Aer_1 599147,551 4463239,714 725,971 
Aer 2 599294,043 4463202,581 706,190 
Aer 3 599567,640 4463570,711 800,754 
Aer 4 599344,798 4464728,404 565,313 
Aer 5 600367,604 4462624,089 683,997 
Aer 6 600475,440 4462533,914 675,667 
Aer 7 599843,005 4461980,968 467,047 
diff X diff Z 
Ikon-Aer_1 3,384 -2,516 -0,947 
Ikon-Aer 2 3,476 -3,463 -1,256 
Ikon-Aer 3 3,698 -4,257 -0,862 
Ikon-Aer 4 4,752 73,951 -0,703 
Ikon-Aer 5 4,011 -3,762 -0,922 
Ikon-Aer 6 3,892 -3,742 -0,263 
lkon-Aer 7 3,749 2,023 -1,187 
Table 2 Differences in Control points with GCP. 
Y Z 
diff_X diff_Z 
Ikon-Aer_1 -0,516 0,984 -0,047 
Ikon-Aer _2 -0,424 0,037 -0,356 
Ikon-Aer_3 -0,202 -0,757 0,038 
Ikon-Aer _4 0,852 -0,451 0,197 
Ikon-Aer _5 0,111 -0,262 -0,022 
Ikon-Aer _6 -0,008 -0,242 0,637 
Ikon-Aer _7 -0,151 0,577 -0,287