11 
per mil. At the beginning epoch of this system we could hardly limit the 
worst value at 1.0 and the average value at 0.5 per mil. But at present 
very rarely we find that this limit attains to 0.7 per mil and we are 
setting the limit of remeasurement at 0.5 per mil of flight distance in 
usual Case. 
Relative orientation is a fundamental process for photogrammetry. 
Until now this process have been submitted wholly to the skill of operator 
and the quality of models could not have been inspected for individual 
models in practice. Now in analytical method, it becomes that the inspec 
tions are free for anyone and for any time. This necessarily guarantees 
the uniformity of the results. If all the models have maintained the 
utmost high quality, it may be said that the errors revealed in the final 
results are not of essential to phtogrammetry, but due to other sources, 
the identification and the ground survey. In this sense the relative 
orientation is the most important process in analytical photogrammetry. 
6. Discussion on absolute orientation 
The routine of electronic computation for absolute orientation, the 
program 4 in our system, is the routine in which mistakes or errors 
concerning the major controls will be detected. 
The program has subroutines in it in which the adjustment of eleva 
tion are done by three different kinds of equations, respectively as 
follows 
(Z1) 
(Z2) 
(Z3) 
Z =-ax - by + c 
Z ^-ak 2 - bx + cy + d 
Z =-ax 2 - bx + cxy + dy + e 
and the planimetrie adjstments are done by two different kinds of equations 
which are the conformal transformation of first and second order as follows 
X = ax t by + X 0 
Y = bx + ay + Y 0 (XY1 ) 
X = ax - by + c(x^- y2) _ 2dxy + X 0 ( YY? \ 
Y = bx + ay + d(x*- ) - 2cxy + Y 0 
We are of opinion that the equations for adjustment, in other words 
the transformation equations for absolute orientation, would be as simple 
as possible and we would not like to use the third order conformal trans 
formation for planimetry, and for elevation we use the equation of (Z3) 
only for the case where' there are many level points distributing at both 
sides along the strip, as the equation has a cross term and only it is