"Jack Erbes" wrote in message
...
Andy K. wrote:

snip

I would proceed with caution using any of the "superior" Garmin charts.
Just
in our local waters we have found several errors that will cost you
dearly
if you don't test the waters before you trust their charts.


Were the errors unique to the Garmin chart chip or was the same error
found on a USGS or NOAA paper chart?

I think all the companies making chart chips for U.S. waters start with
the same data (from USGS or NOAA sources) and then they make vector or
raster charts based on that data. So if you find errors on a chart chip
and can look at the chart it was based on, you may see the error there
too.

Jack

--
Jack Erbes in Ellsworth, Maine, USA - jacker at midmaine dot com

The errors that were found involve markers in the channel leading through
the bayou where I work. it is possible that the markers were replaced after
hurricane Opal in '95. We don't use the chart chips to navigate because we
have extensive knowledge of the local waters and can run using visual cues
or radar.

I have never checked the marker positions against those on the current
charts and would not be surprised if they were off.

Chart plotters and chips are fine, but we never use them as a primary means
of navigating any boat we crew. Our captains will use a combination Nobeltec
software along with paper charts during most trips.

I'm not out to slam Garmin or anyone else as I have a bunch of their
equipment installed on our boats and boats belonging to our customers. All I
can say is don't let the electronics do all the thinking for you.