the area of large and very large scale mapping 
magnetic tapes - when digitizing directly from the oriented 
  
stereo model in a contour mode, it is necessary when recording 
a large amount of information e.g. the digital codes, subcodes, 
X, Y and Z, to record directly onto magnetic tape. 
a midi computer - the mini or midi computers of the '70s are 
  
able to handle many of the data processing requirements which 
during the !60s were thought to be only the domain of the maxi 
computers, The mini computers are becoming more plentiful, 
more versatile, less expensive, faster, more accessible, ete., 
and lend themselves very well to a serial processing of data. It 
is the contention of our Office that the midi computer system 
offers the optimum versatility for the solution of the map-making 
process. 
light beam drafting - we must produce a product which is "equal 
  
to or better than" that which has traditionally been produced by the 
  
photogrammetric draftsman or cartographer. The only way this 
can be obtained with present day hardware is with light beam 
drafting equipment, Any mechanical contact between the carriage 
of the automatic coordinatograph and the drafting material has 
definite limitations,