[jerryRiggin]

We sailed around the northern part of eastern Andros a few years ago and the reefs there are really dangerous. They pop up out of nowhere!
I was checking out that area on my map for a trip we're planning and it's really amazing the difference in the map versions (see image below)... anybody used Navionics maps in the Andros? Pointers?

 

[killarney_sailor]

Something else to consider is that different e-chart makers have licensed proprietary data. Don't know if it has changed now, but Garmin had licensed the Explorer Charts data for the Bahamas which is superb and Navionics had not. So Garmin is (was?) the way to go in the Bahamas.

In the Eastern Caribbean, Navionics had licensed the Imray/Iolaire data so they had the upper hand there.

It is interesting when the paper chart debate happens that people go on at length about how wonderful and accurate paper charts are. I get a sense that they have not been off the beaten track where you get paper charts like the one on the left. In more remote areas, hydrographers focussed on areas that were of interest to navies and commercial shipping and had little interest in the shallow little bays that are interest to sailors. We anchored in a bay in southern Indonesia that was about a mile across. There was one sounding in the middle that was something like 7m. That seemed pretty good so we went for it while keeping a close eye on the sounder. When we got there it was about 12 m deep. We kept heading towards shore for a quarter mile or so until we got to 5 m or thereabouts. In another place we were anchored a couple of hundred metres on land. When we left in the morning, we were in water too deep for the sounder but still on land according to the chart. Much of the world has not been surveyed.

 

[Yorksailor]

We have used Navionics from Northern Canada to Trinidad and three times around the Caribbean and find them excellent value...We also have Open CPN...similar sized errors but just different depending on the source chart.

Once you leave Miami/Key West they are not reliable for close navigation, we have seen errors of up to 500 yds. The reason is that the Bahamas were last charted using sextants and the charts that Navionics are derived from, which may be 50+ years old, are not accurate. Coral and mangroves grow and hurricanes move sand!

Explorer charts are better but still in the Bahamas it is all visual navigating in good light. We see 1-2 boats per year on reefs because they believed the chart plotter.

Enjoy Phil

 

[bvander66]

Past 5 years in Bahamas have relied on Explorer with no faults or errors noticed.
Garmin and C-Map have incorperated Explorer into their echarts, Navionics has not.

In the past two years we have heard reports of cruisers running into trouble with Navionics.

 

[Vasco]

Definitely do not rely on Navionics in the Bahamas. I pointed out a whole lot of errors to them but they will not tell me whether they have corrected them. I have two of their chips of the Bahamas. The older 2004 one is better than the 2014 one as they had to remove proprietary data from the newer chips that they had "borrowed" from Explorer. If you foolishly rely on Navionics in the Bahamas it will take you over islands! I am stuck with Navionics because I have a Raymarine plotter but I certainly do not rely on it.

For paper in the Bahamas use only Explorer charts. For electronic Garmin or C-Map who both use Explorer data.