dx 
20 
intersected coordinates due to the inclinations of the photographs 
under the conditions assumed 
h ha hg ha 
3 4 t y (93 — dey) + S57 (doy — doy) + ope — V) (do, — dex) (55) 
h ha” hj hy. 
= 2 do, == 2 p (des res do) + 2p (des "E dq) + 2p? (y TT ) (des =r do) (56) 
If the corrections dq, do, dy, and dw, are known, the preliminarily 
intersected coordinates x and y evidently can be corrected according to 
the formulae (55) and (56). The d?fferences between the longitudinal and 
the lateral inclinations of the photographs are under normal conditions 
of special interest. Such differences can conveniently be determined 
from y-parallax measurements. See for instance HALLERT 1956. 
If the intersected coordinates are transformed to the coordinate 
system of the ground with the aid of two translations, one rotation and 
one scale change (see the differential formulae (17) and (18) above) 
the three first terms of the formulae (55) and (56) evidently will become 
automatically compensated. From the direct comparison between the 
  
expressions (17)—(18) and (55)—(56) respectively we find the relations 
h 
da, = 3 do, (57) 
h 
dy, ET dw, (58) 
db h E 
b = Ya (dq 2 71 dq) (59) 
h 
dx = — > b (do, — do) (60) 
Only the last term of (55) and (56) cannot be entirely compensated 
in this way. The magnitude of these terms evidently depends upon the 
magnitude of the factor y" — y' which is the y-parallax in the actual 
point. 
The formulae (55)—(56) evidently are valid only for comparatively 
small inclinations and inclination differences. For larger angles among 
other things the full trigonometric functions of expression (44) have to 
be used. In principle, a similar discussion as above can be used.