valid for the case that the torsion of a strip is not of mere appearance, 
but of confirmable as a systematic reality. 
The residual errors at major controls are, in strict sense, the 
relative errors between photogrammetry and ground survey. And there are 
the errors which belong neither to photogrammetry nor to ground survey, 
the errors of identification. So there are three different kinds of 
errors or mistakes which have to be detected in the phase of absolute 
orientation. In our system detected results are at once fed back to the 
corresponding section, and inspections and remeasurements will be made 
thoroughly for the point concerned. This system was much effective for 
the improvement of the quality of the results. Of course the final results 
can not be improved without the improvements of each branch of operations, 
the measurement, the identification aad the ground survey. And the pro 
gresses of each branch were being made step bystep separately but not at the 
same rate. The steady progress might not be made without the quick feed 
back of mistakes by computer, and it revealed that, although the progresses 
of the separate branches are not uniform, but always are drawn up by the 
progresses of other branches. Because, as the progress of the final 
results of absolute orientation can only be made with the uniform and 
balanced progresses of each branches, the delay of progress of one 
particular branch is always pointed out as peculiar. 
There is one thing to be mentioned here about the identification of 
major control. Identification is a very important operation in photo 
grammetry without which the photogrammetry could not be useful in practice. 
In spite of the fact, this procedures are very frequently being the main 
cause of errors which bring into the whole system confusions. As well 
known, even in the case where there are signals at controls, there often 
occur misidentifications. And in the case when the identifications 
are done by pricking in the field, very many times we are confused by the 
troubles caused by the misidentifications by pricking. The identification 
is a difficult operation and often it is recommended that the operator 
have to be selected from the skillful photogrammetrist, but in our 
factory it was difficult to pick up skillful photogrammetrist from the 
operator of plotting machines, and very long time it got into a habit that 
the work of identification by pricking shall be put into the domain of field 
surveyor, ignoring the importance of the operation. The introduction of 
analytical system completely exposed the inadequacy of the system 
adopted hitherto. And after excited discussion the work of identification 
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