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Personnel training problems are more critical with this type of 
equipment for two reasons. First, the operator must be familiar with 
computer operation as well as the photogrammetric operations of the 
instrument. Second, most efficient exploitation of this instrument 
is achieved by a proper blending of numerical and analog techniques. 
More than ever, an operator must be familiar with analytical photo 
grammetric theory - a requirement formerly reserved only for key first 
order instrument operators in a line organization. 
To make maximum utilization of the Black Box Program it is 
desirable to have an auxiliary computer system available to 
compute the least squares solution for its coefficients. This involves 
computer scheduling problems to make such computations in a timely 
manner. 
l4. Operations Performance Factors 
With the experience acquired so far at ACIC, several statements 
can be made about expected performance of the AP--2 in future operations. 
As far as basic precision is concerned, the present AP-2 
prototype does not equal the precision of,say the Wild A-7 • Witness 
the AP-2 grid test precision of C ~ 5000 as opposed to C ~ 10,000 
for an A-7 model magnification of 2:1. (The disparity is attributable 
to the difference in model magnification scale.) This limitation on 
basic precision is electronic in nature and can be improved by decreasing 
the basic 5p increment to 2 l/2|_i off of the hand and foot wheels at 
the expense of slew speed. On the other hand, when working with 
average wide angle cartographic materials, the AP~2 performs as well 
as the A-7. Consequently, it is our opinion that under normal 
conditions, the AP-2 will perform with the same accuracy as present 
available first order equipments. 
In the comparison of operation times to conventional instrumenta 
tion, the AP-2 does not show any significant advantages. What is 
gained in the use of its automatic features in relative and absolute 
orientation is lost in computer set up and tape preparation Also, 
the need for the operator judgement is not eliminated with such 
automation. Since the least squares process of relative orientation 
pre-supposes a given math model, it is still the responsibility of the 
operator to determine any deviations from the model and improve his 
solution accordingly. If the Black Box solution is used, actual model 
set up time may take longer than present procedures, but with an 
accompanying improvement of accuracy. 
As far as compilation time is concerned, no improvement is 
expected since procedures on the AP-2 parallel what is presently 
being done on conventional instruments.