Navionics charts any good for Bahamas after their 2018 revisions?

[hoiwurff]

Hi sailors,

Does anybody have experiences from the last 3 years using Navionic maps in the Bahamas?

The concensus (and my own experience in the Exumas) was always that "Explorer maps" were the only way to go and that Navionics was not suffient.

Apparently Navionics improved their charts in the Bahamas ( https://www.navionics.com/usa/blog/p...harts-released ) since then. I just wanted to check if anybody had experience since then using their chart navigating in the Bahamas. I am currently using the Navionics charts on my Raymarine chartplotter in the Caribbean, so it would be easy for me to just stick with that when heading into the Bahamas later this year.

Specific questions I have:
- Are the Navionics charts now useable for detailed navigation and exploring the Bahamas?

- What Chartplotter maps use the explorer maps- I heard C-Map. Can anybody confirm? I could buy these to use on my Raymarine Axiom if needed.

- Are there any good apps a la Navionics app, for secondary navigation and trip planning that use the Explorer maps?

Thanks for the help!
Marcel

[Geoff54]

https://www.explorercharts.com/electronic-data

[chris mac]

My navionics on axiom is 1 year old. It works great for the East coast. In Bahamas explorer charts on the aquamaps app, on my tablet, is far superior

[team karst]

I am currently giving aqua maps and explorer a shot. Currently a Navionics user. In the past, a explorer paper chart user. All Bahamas in my study area.
At first glance, aqua map is missing entirely a harbour that we go into. This is one that navionics has some misplaced reefs, but at least it has the actual destination. OTOH, navionics seems to have a pessimistic view of depths, so, this works out to be a multiple source dataset.

[Jon Hacking]

We have not found ANY commercial charts that are adequate (for SE Asia). Therefore, we've been making high-quality, high resolution charts from satellite imagery since 2014. They're incredible, as the geo-registration is probably better than your GPS. Max errors are on the order of 10' or 3m. You can see individual coral heads & they're exactly where they're supposed to be.

The tools & data are all free on the web, but it does take significant time & internet bandwidth to download the content. We use SAS Planet to download the content, & Sat2Chart to automate the process. SAS caches all downloaded data on your hard drive, so it's available for offline access later.

Basically, we:

• Draw routes around archipelagos or along the sides of larger land-masses.
  
• Export those routes to a folder.
  
• Feed those routes to Sat2Chart. Tell it how far you want to collect on the sides of your linear routes (it will collect all data inside closed routes), what maps you want to download data from, & what zoom levels you want to download (we use Z10-Z18).
  
• Sat2Chart will then fire up multiple instances of SAS Planet to download the content & make mbTiles of that downloaded content. For large areas (I recently did the entire eastern Caribbean) it can work for days, but it does this all automagically, with no further human input.

SAS gives access to LOTs of satellite imagery. We use ArcGIS (fabulous), Bing (Microsoft), & Google Earth, but there are others available, like Nokia.

But even better, SAS gives access to the latest CMap & Navionics nautical charts as well. These aren't as accurate, of course, but they do have depths.

I usually finish by making a big mbTile of the whole area (like the Bahamas, or the eastern Caribbean) so I can feed that to OpenCPN, but you can also create AT5 files for some chart-plotters.

We tend to run both OpenCPN & SAS, side-by-side on a 17" monitor. Both will take a GPS feed to show where you are, & both can switch between maps with only a single key-stroke, so it's very fast to find which chart is the best for your area. If you want it at your helm, use some free screen-sharing software (TeamViewer) to a tablet.

I've written this whole procedure up in much more detail on our Making mbTiles page. I've tried to write it so even novices can create high-quality charts, so comments & questions are welcome.

[team karst]

Good post but Bahamas is not in SE Asia.

[Jon Hacking]

Originally Posted by team karst

... Bahamas is not in SE Asia.

Really, Karst?

The USGS makes some pretty good charts. Since they're made with US tax dollars, they're available to the public for free, & OpenCPN provides a way to automatically download them as they get updated.

But Bahamas is not the in the US.

We happened to be in SE Asia when I started this project. While we haven't sailed to the Bahamas to check the local charts, I strongly suspect that the charts for the Bahamas are not significantly better than the charts for SE Asia.

[CapnCuervo]

We have been cruising in the Bahamas the past 70 or so days, and I have the latest Navionics charts and updates installed on my chart plotter, so I can at least offer an opinion here.

This is what I can tell you. For the most part, the charts and suggested routes have been very accurate and very helpful. The one exception was in the Abacos. I assume that Dorian rearranged the territory, and the depths are no longer accurate. We bottomed out in an area near Elbow Cay that was charted with plenty of depth (“plenty” is a relative term in the Bahamas), and I ended up having to put on a mask and jump in to see what was going on and determine how to get us free. Fortunately, it was just sand and mud, and we were able to work our way loose, but the tide was ebbing, so there was some urgency to the situation.

Since then, we’ve had no issues, but that was a wake-up call.

[ranger58sb]

Originally Posted by hoiwurff

Does anybody have experiences from the last 3 years using Navionic maps in the Bahamas?

There's a relatively recent comparison thread on yachtforums.com. (You can find that.) From reading that, it sounds like Navionics charts for the Bahamas are dangerous.

C-Map and AquaMap are both said to include Explorer charts; no first-hand info on those.

-Chris

[team karst]

Here is one of my recent findings.
Note the liberal use of xxxx on explorer, where Nav has data. This is a 12’ anchorage that explorer wants to keep a secret.
I will say that expl is a bit more user friendly for the high usage routes. Off the beaten path, the story changes.

[LByers]

I'll be watching this thread. I'll be going there in March.

[Sailshabby]

“…But Bahamas is not the in the US.”

Really, Jon? <lol>

[jim King]

Crusing the Exumas in the winter of 2019 I was a good 1/4 mile off the west side of Norma's Cay and headed back to Nassau when we grounded on a very solid sandstone shole which seemed to run for miles in this area. Our chart plotter had indicated we had 6 feet under our keel. The bottom came up fast enough that we hadn't been watching our depth gauge which suddenly showed zero. Most of the area of the Euma Banks are less than ten feet deep and some areas, like the are we grounded in were much less. Fortunately for us it was near low tide and we were able to float off within two hours. I'd not give a lot of credence to your chart plotter and be more careful if sailing at high tide.

[cdcorl]

We tried to use them n 2021. Way too many errors. They can get you close, and will give you the data you need for your plotter while sailing, but you should switch to using explorer charts as soon as you have any question about depth.

[Ranger2727]

Navionicsfor my iPad is great for planning, but leaves a lot to be desired at critical navigation points. Case in point I tried to get in to Scott’s Harbor on Little Exuma Navonics said I had 3 feet at low tide. I tried to enter it at 3/4 high tide, but sounding with a pole revealed only a foot of water where there should have been 4 1/2 feet given tide data. On the other hand my Garmin chart plotter showed the same Harbor as being only full of mangroves and no usable Harbor. Explorer paper charts do not even show the Harbour. A good navigator is always cautious look before you have to swim .