Optional use of ECDIS
position. (Any differences will be most noticeable at grid intersections and during route
monitoring). Where the difference between the local horizontal datum and WGS 84 is
known, an adjustment should be automatically applied by the ECDIS.
Below are illustrated Day and Night colour schemes af a RNC
RNC Display, DAY
44 Facts about chart carriage reguirements
ANNEX III Types of Digital Charts
RNCDisplay, NIGHT
RNC updating
• Updates can be supplied as complete refreshed images or as patches (tiles or areas)
that the RCDS can superimpose on the original RNC. The latter method is normally
used as this minimises the amount of data to be provided;
• Updates are provided in line with those made available for the equivalent paper chart;
and
• Most RNC services currently rely on CD as the transfer media.
Resume of main characteristics of official RNCs:
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