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resources, techniques, and appropriate support. Integration of 
digital systems may require some organizational changes. 
Support concerns the hardware, software, training, documents, etc. 
The hardware of digital systems is simpler than that of the 
analytical systems. Hence, it requires less support. The life-time 
of electric- mechanical and of electronic components is much shorter 
than that of mechanical and optical parts. Hence, the replacement of 
the components should be scheduled accordingly. 
The software support concerns modifications, extensions and the 
corresponding documentation. Digital systems are more liable to 
changes and expansion than the analytical ones. The required 
training for operation and support of digital systems is more 
demanding than that for analytical systems. 
Cost addresses the purchase, operation and support of a system. A 
comparison of the cost for the analytical and digital systems is 
rather ambiguous, because their architectures and capabilities may 
differ widely. Photogrammetric hardware of the analytical systems is 
more expensive than that of the digital systems. The latter, 
however, require in addition extensive image processing software, 
mass- storage devices for images, fast communication lines, powerful 
processors, and high quality image display monitors. The cost of 
some of these components raises exponentially with the increase in 
quality of digital images. 
The software of digital systems is extensive and complex. The price 
is usually high for the few initial generations of the system; then 
it falls considerably. 
At present, it can hardly be anticipated that digital systems would 
cost less then comparable analytical systems. The aim of digital 
systems is, however, to extend capabilities beyond those of the 
analytical systems. 
REFERENCES 
Bertram, S., 1965 
"The Universal Map Compilation 
Equipment (UNAMACE)", Phot. Eng. XXXI, 
No.2, March 1965. 
Cogan, L., Hunter, D., 1984 "Kern DSR1/DSR11 - DTM Collection and 
the Kern Correlator", Kern, Aaran, 
1984. 
Drum, D.E., "Production Experience with 
Elphingstone, G.M., 1978 the AS 11B-X Epipolar Plotter", 
ASP/ACSM, 1978 - Fall Meeting 
Proceedings. 
Helava, U., Seymour, R.H., "The DCCS Automated Mono