GEOGRAPHICAL SURVEY OFFICE OF SWEDEN NO A 34 
21 
Summary. 
The presented solution of the numerical adjustment in the A 7 and A8 auto 
graphs makes both the adjustment of these instruments and the definition 
of accuracy, in practice, possible. A group of 27 points in 3 planes is used 
for solving the problem according to the method of least squares. Because 
the interior and exterior orientations are solved simultaneously, the adjust 
ment can be made in the best possible way. The tolerance limits of the 
adjustment have been solved by means of statistics. Some practical results 
are presented, and all experiments so far carried out confirm the value of 
this method. The same principle can be applied to all analogue instruments 
which have scales for reading the machine coordinates. 
References: 
[1] Kaasila, P.: Numerical Adjustment of the X-obliquity (X-deviation) and 
the Width-error (Y-deviation) in the autographs A7 and A8. 
Svensk Lantmateritidskrift, nr 3, 1964* 
[2] Hallert, B.: A New Method for the Determination of the Distortion and the 
Inner Orientation of Cameras and Projectors. Photogrammetria, XI, 1954, 3* 
[3] lycken, L.E.: Numerical Adjustment of X-Inclinution and Latitude in 
Stereoscopic Plotters, Svensk Lantmateritidskrift, 2-3, 1956. 
[4] Hothmer, J.: Errors in Gimbal Axes. Photogrammetria, XII, 1955-56, 4*