These magnetic tapes then being used for three 
purposes: 
to process through Pass 2 in order to generate 
the plot through to the ADM 
to be used by the maxi computer to generate the 
required digital terrain models, data bases, etc, 
to be stored as the document tape. It would be 
used during this document phase to update all 
other mapping at smaller scales, 
This is primarily a drafting pass whereby the information 
is taken by the computer from the 9-track tape through the 
computer onto the disc, certain amount of unblocking takes 
place, the information is windowed out, the data is screened 
such that the plot being produced on the Gerber 32 table 
will be to the scale, content, density, symbol and area as 
required by the map user, 
For our production of '"tomorrow'' we are investigating the feasibility 
of introducing a "PASS" between Pass 1 and Pass 2 as outlined above. 
This new pass being to place a storage tube, CRT, onto the system such 
that a further edit of the topographic data could take place while the 
1" 
information is in its "volatile" state on the disc. This will involve 
displaying the information on a CRT and interacting with the information. 
Problems such as the crossing of contours can be displayed, analyzed e