tag:blogger.com,1999:blog-4778505478099828368.post6939451386104278681..comments2024-03-21T12:05:02.193+00:00Comments on Crystal Blues: Navionics Sonar Charts & The Missing ReefNeil & Leyhttp://www.blogger.com/profile/05003534197946819046noreply@blogger.comBlogger15125tag:blogger.com,1999:blog-4778505478099828368.post-75467197339847172202018-05-16T19:06:33.864+01:002018-05-16T19:06:33.864+01:00We too have found and reported on problems with Na...We too have found and reported on problems with Navionics charts, both in Mexico [https://sailing-pelagia.blogspot.ca/2016/05/mexico-charts-c-map-versus-navonics.html] and here in Canada. [https://sailing-pelagia.blogspot.ca/2018/05/canadian-nautical-charts-c-map-andor.html]<br /><br />When we were cruising Mexico's Sea of Cortez, C-MAP was somewhat better than Navionics (though I wouldn't be surprised to find the opposites in some areas).<br /><br />I certainly wouldn't trust the Sonar Charts. Interpolating already sparse data and/or including possibly inaccurate crowd-sourced data can't result in accurate results.SV Pelagiahttps://www.blogger.com/profile/14428198462359637369noreply@blogger.comtag:blogger.com,1999:blog-4778505478099828368.post-4476692965681423212017-12-17T07:04:12.909+00:002017-12-17T07:04:12.909+00:00That should read:
‘transited these hazardous area...That should read:<br /> ‘transited these hazardous areas.’Evanhttps://www.blogger.com/profile/05779370849308102179noreply@blogger.comtag:blogger.com,1999:blog-4778505478099828368.post-18673858622027532882017-12-10T21:16:48.187+00:002017-12-10T21:16:48.187+00:00Does it not make sense that crowd-sourced sonar ch...Does it not make sense that crowd-sourced sonar charts would have the most serious data deficiencies around those very shallow areas one would want to avoid? After all, fewer boats will have transmitted these hazardous areas. <br /><br />Therefore, it makes sense to not use sonar charts for navigation deferring instead to official or more robust soundings. (The sonar charts are probably useful to divers & fishing folk but navigators beware...) Evanhttps://www.blogger.com/profile/05779370849308102179noreply@blogger.comtag:blogger.com,1999:blog-4778505478099828368.post-41965789634252433172017-09-16T22:07:42.772+01:002017-09-16T22:07:42.772+01:00Sorry to hear of your crash and happy that neither...Sorry to hear of your crash and happy that neither of you were hurt or the damage significant. <br /><br />We feel that there is a disturbing trend: navigating by tablet with tablet based apps and Navionics charts, or similar. Almost everyone is doing it and virtually every crash we hear about happened with these kind of charts and a tablet being used, sometimes mounted in a bracket, often on some bodies' lap or in their hand. We get two or three crashes a year here in Mexico. Routes, if used at all, were planned on the tablet. Navionics route planning is primitive at best. iNav-x is better, still not great. <br />We have the greatest respect for your seamanship and skills however these crashes, yours included, and particularly Tanda Malaika, were onto a reef or land which is clearly present on the CM93 charts which most people have on their OpenCPN systems. None of the crashes we read about would have occurred had the proper route planning been performed and the yacht been following the planned route. (You would have never plotted a route over that spot on your OpenCpn system at the nav station.)<br />We need to get the word out:<br />Proper navigation includes prior route planning on a proper system with a keyboard, preferably at the nav station, and using the best charts available (part of a navigator's responsibility is to obtain and use the best chart for any given location). After developing the planned route then close inspection, at high zoom levels, is required and corrections made before setting out. Then during the passage the ship's progress along the route must be monitored, preferably by a second person, not the helm's man, and not by referencing a tablet computer in the cockpit. <br />Navigation is made easy with these tools that everyone uses but it is not sound navigation and it is dangerous and anyone who navigates this way will eventually hit stuff.<br />Fred & Judy SV Wings, La Cruz Huancaxtle<br />wingssailhttps://www.blogger.com/profile/13170619136224079532noreply@blogger.comtag:blogger.com,1999:blog-4778505478099828368.post-83778858085794800292017-09-10T12:27:44.172+01:002017-09-10T12:27:44.172+01:00My friend Dana Fowlkes had this to say, via email ...My friend Dana Fowlkes had this to say, via email :<br /><br />" We have had similar experiences with the Navionics Sonarcharts in Thailand and I turned them off. They are worse than useless as they encourage you to think you have data. :(<br /><br />They do not exist for Indonesia and besides, in Indonesia the Garmin and Navionics charts vary between good and off by 3 NMs. No joking. After our first pass through Indonesia, I decided to buy the official ID government electronic charts S63 versions that could be used with OpenCPN. They were amazingly good and were a real benefit to have onboard. Since they are good, then why can't Navionics and Garmin get them? Or at the very least warn us that their charts are fantasy? "<br /><br />Dana, re the Indonesian charts, I had heard from an industry source that some companies have paid for them,others have decided not to. You can figure from this that Navionics have (thus far) made a business decision not to buy the high quality Indonesian data.Neil & Leyhttps://www.blogger.com/profile/05003534197946819046noreply@blogger.comtag:blogger.com,1999:blog-4778505478099828368.post-26321070661765171912017-09-08T18:03:11.674+01:002017-09-08T18:03:11.674+01:00Sure Karl,co-ordinates as follows :
43deg 43.533 n...Sure Karl,co-ordinates as follows :<br />43deg 43.533 north, 70deg 3.039 west<br />Update your Navionics charts online and you'll see that location as it really is. Problem is it seems that most updates in this part of the world will be because somebody hit something. My friend Bill Woodroffe has coined a new democratic descriptor for these charts - he calls them False Views. Just remember, besides the one that I hit, there are lots of these undocumented obstacles out there. Use the government charts if you can.Neil & Leyhttps://www.blogger.com/profile/05003534197946819046noreply@blogger.comtag:blogger.com,1999:blog-4778505478099828368.post-37606383704213942012017-09-08T17:21:42.924+01:002017-09-08T17:21:42.924+01:00Garmin makes their own charts, BlueCharts. Include...Garmin makes their own charts, BlueCharts. Includes updates by GARMIN for LNM Local Notice to Mariner (USCG) and Notice to Mariners NTM (NGA). Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-4778505478099828368.post-64907491846142211262017-09-08T16:32:36.833+01:002017-09-08T16:32:36.833+01:00I'm sorry you had that problem with the charts...I'm sorry you had that problem with the charts. I also have Navionics on an iPad and will be transiting that area over the next couple of weeks. I may have missed it but could you possibly provide the precise coordinates of the issue as well as any location info available for the other chart discrepancies found in the area? ThanksKarlhttps://www.blogger.com/profile/02751666170842220159noreply@blogger.comtag:blogger.com,1999:blog-4778505478099828368.post-65521795442313393682017-09-07T18:32:07.819+01:002017-09-07T18:32:07.819+01:00David - Check out the comment from Robin Kydd, re-...David - Check out the comment from Robin Kydd, re-posted below.Neil & Leyhttps://www.blogger.com/profile/05003534197946819046noreply@blogger.comtag:blogger.com,1999:blog-4778505478099828368.post-57676825509411621262017-09-07T18:31:28.124+01:002017-09-07T18:31:28.124+01:00And just for good measure, this comment from my fr...And just for good measure, this comment from my friend Robin Kydd, who posted on my Facebook link : <br /><br />"You know my opinion of Navionics and as am ex MD of Navionics Australia I write with some authority. <br />Marketing has led the world to believe Navionics is a serious product.<br />Equally disturbing is that C Map Jepperson is now owned by a merchant bank so may also be chasing $ rather that quality any time soon. <br />No electronic chart sold for navigation has any excuse for not being as good as the government charts which in the USA they get free with out copyright issues that hinder good electronic charting in the ex British parts of the world."<br />Neil & Leyhttps://www.blogger.com/profile/05003534197946819046noreply@blogger.comtag:blogger.com,1999:blog-4778505478099828368.post-17287314219677547362017-09-07T18:12:52.553+01:002017-09-07T18:12:52.553+01:00David, C-Map offer professional cartography servic...David, C-Map offer professional cartography services to the maritime industry - they license UK HMO data, among others, and distribute this to the professional maritime industry. If you go to C-Map.com you'll see the two distinct marketing arms of their business. I would certainly trust their charts more than Navionics, though it should be said that I am aware of cases over the years where critical reefs and features have been missing from C-Map and Jepperson cartography. None of these products are perfect, but the large number of Navionics errors is far greater than I have ever seen. To my knowledge Navionics does not have any significant commercial customer base.Neil & Leyhttps://www.blogger.com/profile/05003534197946819046noreply@blogger.comtag:blogger.com,1999:blog-4778505478099828368.post-72807154351345347852017-09-07T17:38:35.016+01:002017-09-07T17:38:35.016+01:00Sorry, I'm not aware of who produces (or updat...Sorry, I'm not aware of who produces (or updates) the charts that Garmin sells. Can anyone assist ?Neil & Leyhttps://www.blogger.com/profile/05003534197946819046noreply@blogger.comtag:blogger.com,1999:blog-4778505478099828368.post-9174446720685680072017-09-07T14:18:39.212+01:002017-09-07T14:18:39.212+01:00Hi Neil. Sorry to hear of the accident. Why is C-m...Hi Neil. Sorry to hear of the accident. Why is C-map better than Navionics? <br />David McKayAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-4778505478099828368.post-47360139874735438312017-09-07T14:05:07.349+01:002017-09-07T14:05:07.349+01:00Do you know if the same defects exist with Garmin ...Do you know if the same defects exist with Garmin GPS marine mapping? Many of us sailors here in the U.S. use Garmin GPS systems.Anonymoushttps://www.blogger.com/profile/11282346786760434396noreply@blogger.comtag:blogger.com,1999:blog-4778505478099828368.post-21964014483346854052017-09-07T13:22:50.577+01:002017-09-07T13:22:50.577+01:00Receiving quite a lot of stories from other sailor...Receiving quite a lot of stories from other sailors who have found missing data in the standard Navionics charts - including one complete island that was missing.Neil & Leyhttps://www.blogger.com/profile/05003534197946819046noreply@blogger.com