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Old 07-10-2011
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Sequitur Sequitur is offline
... a logical conclusion
 
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Quote:
Originally Posted by VetMike View Post
Beautiful! I am curious about where you think the error was? 1.5 miles is a long way off when 10 meters is considered satisfactory for a GPS. Do you think it was the Mexioan charts (many older charts are not accurate), the chartplotter or Goggle Earth? I am asking because there have been reports of grossly inaccurate position date from GPS.
The Mexican charts are notoriously inaccurate. We commonly found uncharted islands, misplaced islands, charted islands that didn't exist, points, rocks and shoals way out of position and many very crude representations of coastlines. In our blog we have often commented on this, sometimes with illustrations, such as: Bahia Concepcion, Baja

Paper charts and chart plotter renderings of the Mexican coast are to be used as rough guides only. To navigate safely there, it is essential that you not trust them, but rely instead on the basics: your eyes, your depth sounder and your common sense. The radar helps jig the chart to the GPS, but from there you use the chart as only a very old, rough sketch.

Sequitur is now in Patagonia, and we have been finding the charts of the Chilean coast very accurate.
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Michael

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