Index Contour 
Intermediate Contour 
Supplemental Contours 
Fills with ticking 
Depressions with ticking 
5601 
56-X 
Spot Elevations 
FEATURE SUBCLASS 
5601 
561X 
Horizontal Control Points 
5618 
562X 
Accurate Locations 
5619 
563X 
Approximate Valves 
5620 
564X 
Location Undetermined 
The advantages are obvious. A filter on 51XX would yield all index contours. A 
filter on 56XX would yield all spot elevations. A filter on 56IX would yield all 
horizontal control points. 
A further optimization would be for these codes to hold for all chart series 
supported by DMAAC. Unfortunately, however, the current specifications for 
each chart series supported by DMAAC have instances where a common feature 
has different symbology requirements. As an example, the requirements for 
symbolic representation of a double line railroad are different in a 1:200,000, 
1:500,000 and even the 1:2,000,000 scale products. The differences are minor 
but currently preclude a capability for maintaining a single GLSS code and a 
single specification file for all chart series. Standardization of symbology to 
support the FOC concept is, of course, desirable but will not be immediately 
achievable. Standardization can only be achieved with user compliance. Based 
on tradition, the potential for personal interpretation by the user, and the 
different requirements of the different chart series, standardization will be 
difficult. 
CONCLUSIONS 
The technical capability for Digital Color Separation of charting products has 
been demonstrated. Procedures are being developed for implementation of this 
capability into the production environment. Equipment and systems projected 
to support future Automated Cartography production requirements, through the 
decade of the Eighties, have been defined and are in development. Also, DMA 
is developing a SLF to support the exchange and storage, on magnetic tape, of 
lineal digital data with the ultimate goal of developing a line segment, noded 
data base (DCAD) for maintenance and archival storage of the lineal digital 
data. Finally, each Chart Product Specification is to be evaluated for its 
potential for standardization to a common symbology. Once having completed 
the development of these efforts, DMA will have the capability for an 
Automated Digital Chart Production System. 
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