Conclusions 
For a convenient correction of space model deformations. on instruments of 
the third order with the space solution it's absolutely necessary to consider 
the elements of external (¢, w and Ax) and inner orientation (dx, dy and Af), 
Mechanical correctional instadlations for these elements arent convenient, be- 
Cause we. can place them directly on the instrument. We can take the elements of 
external orientation from the space aerial-triangulation, the most economical 
method .for the determination of control-points. 
The instruments of the types Stereoflex or Multiscope have the advantage 
over the use of rectified photographs on the stereosketchmaster: We consider the 
elements of orientation more exactly and the working method is shorter too.