In article ,
"Doug Dotson" dougdotson@NOSPAMcablespeedNOSPAMcom wrote:

The digital charts are made from the paper charts.

Actually, all US charts, paper, or digital, are produced
from a common NOAA Digital Database. This database is
available for purchase, by anyone, for a price. (Very High)
The database is always being updated, with new, and or revised
data, but is archived at fixed intervals, for distribution
to the Official NOAA Printers and Digital Chart Providers.
Archival Dates are published with the charts, so that one knows just
when the dataset was frozen for that publication.


Bruce in alaska
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add a 2 before @