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Aqua Map Rant - they hate the green marks!


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I have been up to now a big fan of Aqua Map on my iPad. I just realized that for some insane reason when zooming in and out the green marks vanish way before the red marks! I am not talking zoomed out 100 miles either, this is on scales you would use for navigation and you could easily hit a green mark. I'll have to see about uploading video for a demo. Going into a creek you zoom out and the green mark closer to you vanishes and the red one farther out stays! WTF!!! :angry:

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2 hours ago, Max Rockatansky said:

Maybe you might want to look around instead of at the chart plotter?

Well yes, I do that too, but unlit green cans are not real easy to see in dense fog, night, pouring rain, and so on especially when the chart shows nothing there! A chart plotter that shows nothing but water ahead of you when there are actually obstacles is worse than useless.

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Actually I was messing around just now and isn't just green - it seems to be kind of random depending on where you are.

image.thumb.png.b1c151a7cb1716b8fe43ab39f459fc86.png

 

Now you zoom out just a TINY bit and.............

 

image.thumb.png.ee9a3a3bc85d80e10b2484cb5aa37b3c.png

 

This is an area I know like the back of my hand, but what if I had never been here before :o I no longer consider this safe to use.

 

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32 minutes ago, kent_island_sailor said:

Well yes, I do that too, but unlit green cans are not real easy to see in dense fog, night, pouring rain, and so on especially when the chart shows nothing there! A chart plotter that shows nothing but water ahead of you when there are actually obstacles is worse than useless.

As Team Vestas unhappily proved at high speed in the 2018 VOR...

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Oil in cans - that was a long time ago.

I threw away my old can spout at least 20 years ago.

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*checks*. Yep, still in the tool chest, special car-tools drawer.  For that matter, I still have Great-Grandad's swing-spout oil can that you used to fill from the barrel.

Ya never know...

*checks* Yep, both versions offered on eBay as "antiques."  They're not junk.  They're investments!! 

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Re: the OP - I've never heard of Aqua Map and wouldn't even check it out if I had - sounds like something a newbie with a 40' powerboat would go for.

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41 minutes ago, SloopJonB said:

Re: the OP - I've never heard of Aqua Map and wouldn't even check it out if I had - sounds like something a newbie with a 40' powerboat would go for.

It was actually really well reviewed on Panbo, can download the latest depth surveys, and does all kinds of cool things. I was really liking it until I realized what it did with vanishing marks.
Meanwhile the Navionics app has better colors, but has a much worse AIS implementation. It also cannot do anything but north up on an IOS device, but at least it doesn't hide solid objects :rolleyes: The crowd-sourced depth surveys are pretty cool too, depending on how much you trust them.

 

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2 hours ago, Max Rockatansky said:

@SloopJonBthen what charting app are you using? Garmin quit supporting their excellent BlueChart product, AM is about all there is for iThing plotting AFAIK

It is AquaMap or Navionics for me. I really liked AquaMap better until I noticed this vanishing buoy thing.

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8 hours ago, kent_island_sailor said:

Well yes, I do that too, but unlit green cans are not real easy to see in dense fog, night, pouring rain, and so on especially when the chart shows nothing there! A chart plotter that shows nothing but water ahead of you when there are actually obstacles is worse than useless.

I was trained to see green cans (and red cans and cardinal marks) as being like signposts or road markings, rather than obstacles.  I even keep an old pair of Mark 1 eyeballs on board to spot them.

But that training was back in the days of rotary dial telephones, and call-the-operator to connect to make long-distance calls. In this brave new world where a tablet is a paperback-sized magic computer rather than a we dose of medicine or hallucinogens, maybe that has all changed ... but the old ways still work for me.

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4 hours ago, Max Rockatansky said:

@SloopJonBthen what charting app are you using? Garmin quit supporting their excellent BlueChart product, AM is about all there is for iThing plotting AFAIK

I'm not - I only use my boat locally so no need.

When I cruise it's on a friends boat with a big Raymarine plotter at the helm.

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1 hour ago, TwoLegged said:

I was trained to see green cans (and red cans and cardinal marks) as being like signposts or road markings, rather than obstacles.  I even keep an old pair of Mark 1 eyeballs on board to spot them.

But that training was back in the days of rotary dial telephones, and call-the-operator to connect to make long-distance calls. In this brave new world where a tablet is a paperback-sized magic computer rather than a we dose of medicine or hallucinogens, maybe that has all changed ... but the old ways still work for me.

I am relatively young but still, I learnt with paper map and struggle to make a mental map of what's ahead with electronic maps. Not hitting unlit lateral cans can also be an issue here at night...

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1 hour ago, Panoramix said:

I am relatively young but still, I learnt with paper map and struggle to make a mental map of what's ahead with electronic maps. Not hitting unlit lateral cans can also be an issue here at night...

I there a story there about [not] hitting the cans?

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1 hour ago, TwoLegged said:

I there a story there about [not] hitting the cans?

Yes but sorry I didn't hit anything,

St malo entrance mid 90s, I was a young skipper in his late teens or may be early twenties...

Coming in in under sails at night in a light breeze with a Westerly Centaur, diesel engine not operational (issue with cooling system so at a push I could briefly use the engine but wanted to keep it cool to avoid a marina entrance under sail!), tide not optimal as I got stuck earlier with no wind so was late.

Big grey ship comes from behind and starts flashing his search light like the owner of a Swiss Ferrari who's just discovered French motorways flashes his lights when an old asthmatic Peugeot 205 dares to overtake a lorry (and the Swiss man is not yet aware of French Gendarmes practices of transforming Swiss Ferraris drivers into pedestrians). I call several times alternating French and English on VHF 16, "military ship, this is the small sailboat entering St Malo under sail, do you copy me?" no reply. I start flashing a torch light with some boy scout very slow morse "V H F 1 6 L I S T E N" military ship replies with fast morse I can't understand, he slows down at the last minute visibly annoyed, I can clearly see his big anchor ready to take out my rig. I stay in the middle of the channel as I know that there are two unlit cans I can't spot and anyway a Westerly Centaur is not the best choice to come in zigzaging under sail in light wind in a place with strong currents, so if he pretends not hearing me, he can stay behind. Eventually when the channel widens I change heading and he overtakes me, I realise that it's a French ship. I was really scared of hitting unlit buoys and just wanted to explain my situation and arrange with him a safe overtaking spot... So yes I admit an Ipad would have been helpful in this instance!

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4 hours ago, kent_island_sailor said:

Here you go - see for yourself:

https://www.globalterramaps.com/MBViewer.html?layer=2&pres=2&udw=2&nostore=1&lat=37.13&lng=-97.33&zoom=4

Use the control wheel on the mouse to zoom in and out and watch marks appear and vanish :wacko:

image.png.36775deaf327fef8874889e3cd93baf9.png

 

image.png.dea0656154a9dcf60cb8e9dab81cffa1.png

That's fucking frightening. You can sort of understand some features disappearing as you soon out, but not marks, and not as you zoom in...

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2 hours ago, Panoramix said:

Yes but sorry I didn't hit anything,

St malo entrance mid 90s, I was a young skipper in his late teens or may be early twenties...

Coming in in under sails at night in a light breeze with a Westerly Centaur, diesel engine not operational (issue with cooling system so at a push I could briefly use the engine but wanted to keep it cool to avoid a marina entrance under sail!), tide not optimal as I got stuck earlier with no wind so was late.

Big grey ship comes from behind and starts flashing his search light like the owner of a Swiss Ferrari who's just discovered French motorways flashes his lights when an old asthmatic Peugeot 205 dares to overtake a lorry (and the Swiss man is not yet aware of French Gendarmes practices of transforming Swiss Ferraris drivers into pedestrians). I call several times alternating French and English on VHF 16, "military ship, this is the small sailboat entering St Malo under sail, do you copy me?" no reply. I start flashing a torch light with some boy scout very slow morse "V H F 1 6 L I S T E N" military ship replies with fast morse I can't understand, he slows down at the last minute visibly annoyed, I can clearly see his big anchor ready to take out my rig. I stay in the middle of the channel as I know that there are two unlit cans I can't spot and anyway a Westerly Centaur is not the best choice to come in zigzaging under sail in light wind in a place with strong currents, so if he pretends not hearing me, he can stay behind. Eventually when the channel widens I change heading and he overtakes me, I realise that it's a French ship. I was really scared of hitting unlit buoys and just wanted to explain my situation and arrange with him a safe overtaking spot... So yes I admit an Ipad would have been helpful in this instance!

That's scary, Pano.  Big ship no VHF is very bad news.

Luckily Ireland has too few military ships for them to be much of a problem, and only three significant commercial ports (Dublin, Cork and Rosslare).  Of those 3, Rosslare is the scariest. 

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G.zeus, there were big ships that moved quickly and little ships that didn’t, and unlit marks, all getting along just fine long before the invention of VHF let alone digital plotters.

Go bitch to AquaMaps if you want to have the bug fixed. It’s not like SA or any other fora are going to rewrite the code

Slow down and get a spotlight.

 

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31 minutes ago, TwoLegged said:

That's scary, Pano.  Big ship no VHF is very bad news.

Luckily Ireland has too few military ships for them to be much of a problem, and only three significant commercial ports (Dublin, Cork and Rosslare).  Of those 3, Rosslare is the scariest. 

I did my national service in the navy later, with hindsight I suspect they were pretending to be at war with the VHF in RX only then laughing while listening to the radio and decoding my crappy signals...

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1 hour ago, Max Rockatansky said:

G.zeus, there were big ships that moved quickly and little ships that didn’t, and unlit marks, all getting along just fine long before the invention of VHF let alone digital plotters.

Go bitch to AquaMaps if you want to have the bug fixed. It’s not like SA or any other fora are going to rewrite the code

Slow down and get a spotlight.

 

Genius! All I need is a big light! Just on the off chance that maybe someone else uses this program I thought this might be interesting. My bad.

 

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3 hours ago, European Bloke said:

That's fucking frightening. You can sort of understand some features disappearing as you soon out, but not marks, and not as you zoom in...

The frightening thing is the lack of logic. I get things vanishing as you zoom out, at 100 miles you can't plot everything, but these screen shots are at scales you would user for daily plotting. Even worse it isn't total, it is like every 2nd mark or the starboard ones only or the green ones only or some other insane algorithm :wacko:

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So maybe INavX and quilted raster charts (rip) isn’t such a bad choice. Impossible to over-zoom. What other demons lurk in our ENC/Vector charts? 

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6 hours ago, Panoramix said:

I am relatively young but still, I learnt with paper map and struggle to make a mental map of what's ahead with electronic maps. Not hitting unlit lateral cans can also be an issue here at night...

I am not relatively young and did PLENTY of old school compass and knotmeter navigation. Getting up a pitch dark river in driving rain full of unlit marks was a huge PITA back then. Finding Bermuda crossing sun lines and RDF bearings was a PITA too. I have no interest in recreating 1974 navigation when I don't have to, I think you really appreciate modern tech when you have done without it.

 

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1 hour ago, Panoramix said:

I did my national service in the navy later, with hindsight I suspect they were pretending to be at war with the VHF in RX only then laughing while listening to the radio and decoding my crappy signals...

Those feckers and their war games are a nuisance wherever they are: land, air or sea.

Pano, from what I understand of the history, you must have been one the last batch of coscripts.  Did they train to do anything significant, or were you just scrubbing decks?

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1 hour ago, kent_island_sailor said:

I am not relatively young and did PLENTY of old school compass and knotmeter navigation. Getting up a pitch dark river in driving rain full of unlit marks was a huge PITA back then. Finding Bermuda crossing sun lines and RDF bearings was a PITA too. I have no interest in recreating 1974 navigation when I don't have to, I think you really appreciate modern tech when you have done without it.

 

Thanks for pointing out the error.  Whether you have interest or not, it seems to be slowly (or quickly) becoming impossible to navigate the olde timey way. For example, many of the 4 fathom buoys are getting pulled. Raster charts are getting phased out and if you every tried to print out the printable ENCs, they look like they've been done in crayon. There are few, if any, RDF beacons. Certainly ENC's don't have the land details the way the raster charts have it. I've seen at least one yacht hit something because they believed the, "bathymetric", data in the ENC, though I'm not sure I can blame that on the chart.  Something about relying on one kind of navigational method or device which is becoming harder to avoid. Oh, and I really like the InavX product if you are looking for an alternative. 

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For what it’s worth, I do like the ENC charts, for the most part.  I have an iPad chart plotter on a boat that is my work place.  As I spend time in the 20 knot range, I appreciate that I can run head up in portrait mode and get a good long look at what’s ahead of me.  All the data, like depth numbers, landmark labels and such, get oriented right side up and are readable without having to turn your head.  They also scale and are legible at different zoom levels. It had also been my experience that all the buoys and nav marks also scaled with the zoom, while in raster they got tiny and barely noticeable when zoomed out to any degree.  I also like that I can customize the depth shading, making no-go zones a snap to recognize, and changeable should I bring the plotter to a boat with a different draft.  The only real complaint I have is that buoys aren’t numbered, but now that I’m thinking about it that may be resolvable in the settings.  With AIS integrated right in, easily made and modified routes (I used to have a Standard Horizon where that was an absolute nightmare), I’ll never willingly go back to paper.  I’m using SEAiq, incidentally, as it has features useful for the job the boat does.  Because I have it anyway, it’s also on my phone and other iDevices that I use on recreational boats.  It was $5, and came with free software and NOAA chart updates forever.  Would have paid way more than that and still have thought it worthwhile (the pro version is in fact several hundred, but intended for tankers and container ships and such).

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7 minutes ago, NaClH20 said:

For what it’s worth, I do like the ENC charts, for the most part.  I have an iPad chart plotter on a boat that is my work place.  As I spend time in the 20 knot range, I appreciate that I can run head up in portrait mode and get a good long look at what’s ahead of me.  All the data, like depth numbers, landmark labels and such, get oriented right side up and are readable without having to turn your head.  They also scale and are legible at different zoom levels. It had also been my experience that all the buoys and nav marks also scaled with the zoom, while in raster they got tiny and barely noticeable when zoomed out to any degree.  I also like that I can customize the depth shading, making no-go zones a snap to recognize, and changeable should I bring the plotter to a boat with a different draft.  The only real complaint I have is that buoys aren’t numbered, but now that I’m thinking about it that may be resolvable in the settings.  With AIS integrated right in, easily made and modified routes (I used to have a Standard Horizon where that was an absolute nightmare), I’ll never willingly go back to paper.  For what’s it’s worth I’m using SEAiq as it has features useful for the job the boat does.  Because I have it anyway, it’s also on my phone and other iDevices that I use on recreational boats.  It was $5, and came with free software and chart updates forever.  Would have paid way more than that and still have thought it worthwhile (the pro version is in fact several hundred, but intended for tankers and container ships and such).

Not sure about SEAiq, but on OpenCPN you can set the amount of detail and text you want showing. This is a standard ENC function. I really really love the RNC charts because I grew up on them in paper form and my mind instantly translates that into what I will see. The ENCs I am still getting used to, but as you say they can be manipulated to show you just what you need for your mission. The danger is not realizing how the last guy set things, so if you take your laptop off the Boston Whaler where someone set shallow to 3 feet and onto a tanker where the shallow color should be 30 feet and don't change it........ :o

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2 hours ago, TwoLegged said:

Those feckers and their war games are a nuisance wherever they are: land, air or sea.

Pano, from what I understand of the history, you must have been one the last batch of coscripts.  Did they train to do anything significant, or were you just scrubbing decks?

It wasn't too bad...

At sea I was in charge of the wheel (or joystick to be precise) during my watches and at quay I was in charge of the paint pots store which was convenient as in case of excessive painting duties, I could always claim that the store needed some ordering. We didn't know whether we should cry or laugh the day the skipper ordered us he wanted the ship to shine like "war yacht" but once the Admiral had inspected us, everything went back to normal. As I had my "coastal licence", when we were on diving or demining duties I was driving the RIB so had lot of fun in the swell... It was a 40HP with a tiller and my dinghy experience did transfer a bit too well!

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3 hours ago, kent_island_sailor said:

I am not relatively young and did PLENTY of old school compass and knotmeter navigation. Getting up a pitch dark river in driving rain full of unlit marks was a huge PITA back then. Finding Bermuda crossing sun lines and RDF bearings was a PITA too. I have no interest in recreating 1974 navigation when I don't have to, I think you really appreciate modern tech when you have done without it.

 

Don't think that I claimed that I wanted to go back to dead-reckoning time, I just like a paper map as IMHO it represents better the big picture stuff to look out for, (safe areas, etc...). I am used to OpenCPN which I quite like...

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I noticed the disappearing cans going into St. Michaels this weekend.  What was more frightening was the missing buoy shown on my chartplotter in the Eastern Bay.

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2 hours ago, Panoramix said:

As I had my "coastal licence", when we were on diving or demining duties I was driving the RIB so had lot of fun in the swell... It was a 40HP with a tiller and my dinghy experience did transfer a bit too well!

I guess there are worse ways to spend a year than pottering around arranging paint tins, interspersed with bouts of playing in fast RIBs :)

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3 hours ago, Panoramix said:

Don't think that I claimed that I wanted to go back to dead-reckoning time, I just like a paper map as IMHO it represents better the big picture stuff to look out for, (safe areas, etc...). I am used to OpenCPN which I quite like...

That day is ending, at least in the USA, unless you keep a bunch of old charts around. The print-on-demand ENC charts are horrible and not worth the bother :(

The world is going to electronic everything, I just did a 3,000 mile airplane delivery without one paper chart. We had multiple backups of electronic charts, but people look at you funny if you ask where to buy physical charts.

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40 minutes ago, TwoLegged said:

I guess there are worse ways to spend a year than pottering around arranging paint tins, interspersed with bouts of playing in fast RIBs :)

Yes, it was a small ship so relatively laid back, the man in charge of crew discipline (don't know how you call them onboard English speaking navy ships) was an ex commando, he was super nice and once told me, " full throttle is OK but don't overdo it close to the ship" as he was worried that the commanding officers would ask him to tell me off ;) I suspect he probably did some dirty work for the French state because he was too god at everything to have been in an ordinary unit and he was very discreet about his previous missions except that once he let slip that he could swim out of a submarine and another time that he knew Lebanon, it is tempting to join the dots. Yet he could have taught many HR managers 2 or 3 things about managing people...

So I don't particularly like armies but they did not mistreat me....

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4 minutes ago, kent_island_sailor said:

Wasn't this right after he got into the phone book?

I think that's how the madman played by the most estimable M. Emmet Walsh "found" him. I saw Blood Simple before I saw this, so his role as a killer made sense. 

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7 hours ago, Max Rockatansky said:

Care to elaborate about SEAiq? 

Like I said, for what I paid for it, it’s great.  There are several different versions and price points.  The $5 one was “SEAiq USA”, which includes NOAA charts only for US waters and territories.  To save memory, one can select which zone(s) you want downloaded.  For me in Maine, for example, I’ve just got Block Island to Canadian Border.  Charts are selectable ENC or RNC (for as long as RNC lasts I suppose).  As stated, I prefer ENC, though as noted above it does lack all land detail, which is a shame (and I poked in my home iPad and it does number the buoys.  I may have been thinking of the Furuno chart plotter which also uses NOAA ENC.  Too many danged boats!).  It is originally intended as a tool for harbor pilots, and what I use is basically just a dumbed down version.  You wouldn’t know, other than the insistence to include a readout for rate of turn in one of the drop down tabs (how many boats under 250’ have that?) and an instruction manual that explains at length a great number of features I don’t have.  Beyond that, it’s a basic navigation tool.  It won’t figure the best lay line to the windward mark or do auto routings or have weather overlays.  It will do EBLs and VRMs and a couple other tools I’ve never used.  You can plug a heading and speed and position (and rate of turn  :wacko:) sensor into it, but nothing beyond that.  It does, with internet connection, give tide and current data and local AIS targets even without an AIS receiver (I have yet to figure out what the radius of that is, or where it gets the data, other than users have the option to share it).  I do have a class A AIS with GPS, and I’ve fed that (NMEA 0183) into a little Raspberry Pi running Open Plotter.  That spits out a wifi network which my iPad is logged into, and thus gets gps and AIS data wirelessly.  Perhaps  that’s overly complicated, but it has worked for years reliably so I haven’t changed it.  It looks like this:7001A99D-CBEE-4E42-9F08-50F643A16C28.thumb.jpeg.21c8bf0e928f8205220eddb92f4db226.jpeg

I’m not in Camden, nor even on a boat, but there’s a bunch of live AIS targets banging around.  I dunno.

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Thank you @NaClH20

imma try it.

BlueChart was the best I’ve seen of these things and Garmin are a bunch of fuckers for dropping the support. As if when they initially produced the app they didn’t realize it would compete with their other offerings? FWIW I will not do biz with Garmin, hope they are listening 

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16 hours ago, NaClH20 said:

Like I said, for what I paid for it, it’s great.  There are several different versions and price points.  The $5 one was “SEAiq USA”, which includes NOAA charts only for US waters and territories.  To save memory, one can select which zone(s) you want downloaded.  For me in Maine, for example, I’ve just got Block Island to Canadian Border.  Charts are selectable ENC or RNC (for as long as RNC lasts I suppose).  As stated, I prefer ENC, though as noted above it does lack all land detail, which is a shame (and I poked in my home iPad and it does number the buoys.  I may have been thinking of the Furuno chart plotter which also uses NOAA ENC.  Too many danged boats!).  It is originally intended as a tool for harbor pilots, and what I use is basically just a dumbed down version.  You wouldn’t know, other than the insistence to include a readout for rate of turn in one of the drop down tabs (how many boats under 250’ have that?) and an instruction manual that explains at length a great number of features I don’t have.  Beyond that, it’s a basic navigation tool.  It won’t figure the best lay line to the windward mark or do auto routings or have weather overlays.  It will do EBLs and VRMs and a couple other tools I’ve never used.  You can plug a heading and speed and position (and rate of turn  :wacko:) sensor into it, but nothing beyond that.  It does, with internet connection, give tide and current data and local AIS targets even without an AIS receiver (I have yet to figure out what the radius of that is, or where it gets the data, other than users have the option to share it).  I do have a class A AIS with GPS, and I’ve fed that (NMEA 0183) into a little Raspberry Pi running Open Plotter.  That spits out a wifi network which my iPad is logged into, and thus gets gps and AIS data wirelessly.  Perhaps  that’s overly complicated, but it has worked for years reliably so I haven’t changed it.  It looks like this:7001A99D-CBEE-4E42-9F08-50F643A16C28.thumb.jpeg.21c8bf0e928f8205220eddb92f4db226.jpeg

I’m not in Camden, nor even on a boat, but there’s a bunch of live AIS targets banging around.  I dunno.

I must be doing it wrong. The one I downloaded has pretty amazing capabilities... but it wants $50

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On 7/27/2021 at 6:46 AM, kent_island_sailor said:

The frightening thing is the lack of logic. I get things vanishing as you zoom out, at 100 miles you can't plot everything, but these screen shots are at scales you would user for daily plotting. Even worse it isn't total, it is like every 2nd mark or the starboard ones only or the green ones only or some other insane algorithm :wacko:

From time to time people pay me to see that software is created so I know a thing or two from the inside.

A major theoretical problem with GIS visualization software, of which chartplotter applications are but one of many examples, is presenting as much detail as possible without excessive clutter.  Traditional, human-brain-guided cartography handles this tedious process on a case-by-case basis -- areas with little to show get more trivial details while complex areas get only highlights.  For land-based GIS, a similar process is followed in software by detecting the collision of marks and labels and having some sort of hierarchy, some sort of rules, and some sort of balancing that goes on to produce useful results.

ENC visualization software does the same thing to some degree, as it must to produce readable results.  In properly written visualization software, buoys and obstructions are one of the last things to go as you zoom out, and that has been my experience with Garmin handheld GPS, and Navionics, and OpenCPN.  In properly written software the cans and nuns should all disappear at once rather than a soft decluttering algorithm being applied.

As for Aquamap, well, the behavior you describe is probably intentional.  Perhaps it is an ill-considered decision made by someone who lacks any practical navigation experience.  It would then be an example of why good companies try to hire software developers who have experience with the industry or application for which the software is being developed.

More broadly, I agree that the discontinuance of RNC charts is premature as the quality of the ENC visualizations is simply not high enough yet.  It takes forever zooming in and out to get the whole picture, even with a large, high-resolution display.  The density of information cannot yet approach that of traditional cartographic methods.

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On 7/27/2021 at 9:41 PM, Max Rockatansky said:

Thank you @NaClH20

imma try it.

BlueChart was the best I’ve seen of these things and Garmin are a bunch of fuckers for dropping the support. As if when they initially produced the app they didn’t realize it would compete with their other offerings? FWIW I will not do biz with Garmin, hope they are listening 

You’re welcome!  My (admittedly, limited) experience with Garmin is that they will support their products for a generation or two and then drop them for the latest and greatest.  Perhaps that is no longer the case; I don’t know.  I was soured on them once and thus will no longer consider their products (listening, Garmin??   And everyone else?).   I have Furuno equipment dating to 1996 that still works and still gets factory support, so anything new will come from them or a similar company.  I’ll spend the extra boat bucks for that, thank you.

 

And SEAiq USA is still $5?  I shoulda checked that.  Something in the back of my head says that someone told me he raised his prices but I never looked.  That’s another thing…. I emailed an operational question once, and got a detailed answer from the guy who wrote the software before noon the next day.  Pretty good service if you ask me.

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On 7/26/2021 at 9:33 PM, TwoLegged said:

I was trained to see green cans (and red cans and cardinal marks) as being like signposts or road markings, rather than obstacles.  I even keep an old pair of Mark 1 eyeballs on board to spot them.

But that training was back in the days of rotary dial telephones, and call-the-operator to connect to make long-distance calls. In this brave new world where a tablet is a paperback-sized magic computer rather than a we dose of medicine or hallucinogens, maybe that has all changed ... but the old ways still work for me.

Not sure if I have kept on things enough, but it still my understanding that the Mk 1 eyeball is still a requirement for colregs and basic safety at sea?  I believe over on the land side, an officer might cite you for 'driving unsafe for conditions'?  Radar, AIS, ChartPlotters off your cel phone - all great.  Meanwhile still inadequate.  Oh yeah - and listening for gongs :)

Edited by DriftingWithoutGrifting
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8 hours ago, DriftingWithoutGrifting said:

Not sure if I have kept on things enough, but it still my understanding that the Mk 1 eyeball is still a requirement for colregs and basic safety at sea?  I believe over on the land side, an officer might cite you for 'driving unsafe for conditions'?  Radar, AIS, ChartPlotters off your cel phone - all great.  Meanwhile still inadequate.  Oh yeah - and listening for gongs :)

I am not sure I understand your post? If you are saying no one can just stare at a screen and never look outside, that is quite true.

If you are implying that all waterborne commerce halts in bad visibility, that is quite false and always has been. Watching a freighter put the hammer down and go under the Bay Bridge in fog so thick they surely could not see the bow and I could only see the upper bits of the ship from the bridge as she passed at about 18 knots or more was quite impressive and would have made a great video to sell AIS or radar sets!

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18 minutes ago, kent_island_sailor said:

Watching a freighter put the hammer down and go under the Bay Bridge in fog so thick they surely could not see the bow and I could only see the upper bits of the ship from the bridge as she passed at about 18 knots or more was quite impressive and would have made a great video to sell AIS or radar sets!

Surely that was illegal as the COLREGS are quite specific about adopting a speed appropriate for the visibility (probably phrased differently as I leant it in French).

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8 minutes ago, Panoramix said:

Surely that was illegal as the COLREGS are quite specific about adopting a speed appropriate for the visibility (probably phrased differently as I leant it in French).

I thought that too, but that doesn't help if they run you over :rolleyes:

* that is an issue with AIS, once a lot of people have it some skippers/pilots get the idea everyone does or they don't matter. I know watching a center console go by at night at 30+ knots with the skippers face lit up brightly by his multiple undimmed screens that if you don't show up on is TV set, you don't exist :o

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3 minutes ago, kent_island_sailor said:

I thought that too, but that doesn't help if they run you over :rolleyes:

* that is an issue with AIS, once a lot of people have it some skippers/pilots get the idea everyone does or they don't matter. I know watching a center console go by at night at 30+ knots with the skippers face lit up brightly by his multiple undimmed screens that if you don't show up on is TV set, you don't exist :o

I can't disagree with you, there is no point in being a dead law abiding mariner!

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Systems that give you AIS when you don't have it on your boat do it by getting it off the internet.  So you need to have an internet connection(cellular) and where ever they are getting the data from has to have a shore site or satellite that is picking up and retransmitting the data. Marine Traffic displays a lot of ships.  I have used it with my cell phone in Long Island Sound about 5 years ago.  It doesn't work so well in areas that don't have the stations.  And I don't know if you have to pay for the satellite data.

 

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2 hours ago, seaker said:

Systems that give you AIS when you don't have it on your boat do it by getting it off the internet.  So you need to have an internet connection(cellular) and where ever they are getting the data from has to have a shore site or satellite that is picking up and retransmitting the data. Marine Traffic displays a lot of ships.  I have used it with my cell phone in Long Island Sound about 5 years ago.  It doesn't work so well in areas that don't have the stations.  And I don't know if you have to pay for the satellite data.

 

Besides for all that there is a time delay. Given how easy it is to add an AIS receiver now I cannot imagine trying to rely on incomplete time-delayed internet fed AIS.

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Well, plus internet AIS is over with.  Nobody offers anything near real time without a paid subscription.  Which costs more than an AIS unit.  

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32 minutes ago, toddster said:

Well, plus internet AIS is over with.  Nobody offers anything near real time without a paid subscription.  Which costs more than an AIS unit.  

$100 AUD for a cheap Chinese combined AIS/GPS unit that can output via NMEA0183 & RS232.

Probably a POS but cheap.

FKT

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14 hours ago, Fah Kiew Tu said:

$100 AUD for a cheap Chinese combined AIS/GPS unit that can output via NMEA0183 & RS232.

Probably a POS but cheap.

FKT

If you are really cheap, you can get for 20€ a SDR dongle that you plug in a PC. OK if you don't have a PC, you need a raspberry Pi and a screen and that tips it in favour of the chinese tat.

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29 minutes ago, Jim in Halifax said:

C'est quoi ça, une SDR?

I'm thinking the easiest way for me to get in the game is an AIS enabled VHF...

SDR stands for software defined radio and basically a fair bit of the expensive hardware of 1980s style radios becomes cheap software. 

En français on dit radio logicielle.

 

https://www.rtl-sdr.com/buy-rtl-sdr-dvb-t-dongles/

 

 

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2 hours ago, Panoramix said:

If you are really cheap, you can get for 20€ a SDR dongle that you plug in a PC. OK if you don't have a PC, you need a raspberry Pi and a screen and that tips it in favour of the chinese tat.

I have one - a dAISy hat for a Raspberry Pi. I have quite a lot of Raspberry Pi computers, I like them.

But that's a bit of a PITA solution as you then need to screw around a lot to get the data out over Ethernet. Fine if everything you want to do is on the Pi. I can do socket level programming. Doesn't mean I want to. I have a Pi 4 with 18" screen on the bulkhead of the cabin to run OpenCPN. Separate dedicated Simrad plotter at the wheel. Feeding it data via Ethernet is simple.

Assuming it works, the Chinese box with both GPS and AIS requires an antenna, power supply and wiring the TX and ground pins to the DB9 port on a single port terminal server with Ethernet plugged into the other side. Presto, gps and ais data over Ethernet.

A lot of the commercial AIS have NMEA0183 ports which are basically RS422/485 and their output can also be sent to a terminal server. NMEA2K is a different problem.

Why do I want the data on Ethernet? Because both NMEA0183 and NMEA2K suck dog balls IMO. I've already solved the gps side about 3 separate ways, now looking at the simplest/cheapest (not necessarily the same) way to deal with AIS reception. Were I going to broadcast my position as well as listen I'd buy a decent commercial solution, same as I did for my Simrad plotter. This is just playing.

SDR - software defined radio. In essence a radio receiver where the frequency can be set by software. Pretty neat devices.

FKT

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I wouldn't bother with the completely networked solution because I am too lazy and not competent enough to maintain such a system on a boat! OK may be if I was sailing singlehanded with a crappy autopilot (but then I would sort out the autopilot first!)... One screen below deck linked to a single raspberry Pi that does OpenCPN, GPS, AIS possibly linked to a SSB receiver to do weatherfax and possibly again Navtex is complicated enough for me. Have a spare Raspberry on board with a spare SD card that is identical to the main one, when something is wrong you swap...

But then I am not a software engineer...

 

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1 hour ago, Panoramix said:

I wouldn't bother with the completely networked solution because I am too lazy and not competent enough to maintain such a system on a boat! OK may be if I was sailing singlehanded with a crappy autopilot (but then I would sort out the autopilot first!)... One screen below deck linked to a single raspberry Pi that does OpenCPN, GPS, AIS possibly linked to a SSB receiver to do weatherfax and possibly again Navtex is complicated enough for me. Have a spare Raspberry on board with a spare SD card that is identical to the main one, when something is wrong you swap...

But then I am not a software engineer...

 

Yep, fair comments. I like playing with this sort of stuff, used to do it for a living.

All I really need is my Simrad MFD and the IKonvert box feeding depth data from the NMEA0183 depth transducer to the NMEA2K network that the Simrad requires as input. I wanted a display at the wheel and couldn't solve the OpenCPN/Raspberry Pi display issues - waterproof touch screen at 1000+ nits brightness. You can get them but by the time you buy one, the Pi, all the other bits, I was within $400 of the price of the Simrad MFD. Decided it was a problem better avoided by throwing money.

I've got Navionics on a couple of tablets, it works quite nicely really. Never heard of Aqua Map before this thread. Costs $30 AUD a year for Navionics, that's noise level.

FKT

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I have SEAiq fired up now. It uses the same RNCs and ENCs as OpenCPN, so I can have the nav computer and the iPad looking at the same charts in the same way B) I still am not a huge ENC fan, but that is the future like it or not.

AquaMap is off the iPad, now I know it hides buoys I can't trust it. Navionics might stay, maybe they'll fix their rotation issue. Their AIS implementation still sucks balls :(

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10 hours ago, kent_island_sailor said:

I have SEAiq fired up now. It uses the same RNCs and ENCs as OpenCPN, so I can have the nav computer and the iPad looking at the same charts in the same way B) I still am not a huge ENC fan, but that is the future like it or not.

AquaMap is off the iPad, now I know it hides buoys I can't trust it. Navionics might stay, maybe they'll fix their rotation issue. Their AIS implementation still sucks balls :(

I don't have AIS yet so can't comment. I did find that I could get Navionics on the tablet to connect to the Simrad wifi without dramas. Then it uses the Simrad gps rather than its internal one with a power saving, plus gets the depth data and updates its bathy map as you travel about. That's quite useful I've found. Especially given my habit of poking into places marked as shoal on the maps...

FKT

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3 minutes ago, Fah Kiew Tu said:

I don't have AIS yet so can't comment. I did find that I could get Navionics on the tablet to connect to the Simrad wifi without dramas. Then it uses the Simrad gps rather than its internal one with a power saving, plus gets the depth data and updates its bathy map as you travel about. That's quite useful I've found. Especially given my habit of poking into places marked as shoal on the maps...

FKT

AquaMap, Navionics, and SEAiq all read my GPS/AIS data stream over the wifi no problem. My iPad has no internal GPS. I need to do some wiring changes to get depth onto the wifi.

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Just now, kent_island_sailor said:

AquaMap, Navionics, and SEAiq all read my GPS/AIS data stream over the wifi no problem. My iPad has no internal GPS. I need to do some wiring changes to get depth onto the wifi.

Funny/annoying thing is, the Simrad running C-Map doesn't update *its* bathy data. There may be a setting for that, might have to RTFM again. I don't really like the C-Map software but getting Navionics for the plotter, while possible, costs $$$ I'm not willing to pay.

Oh well once I 'finish' playing with the Pi/OpenCPN stuff for the cabin maybe it will also update the bathy data though I doubt it unless there's an extra GIS layer for user-provided data. I've a bit of Java code recording time, lat/long and depth already, basically my cruise track at 5 sec intervals.

Being stuck in lockdown in Sydney means I have more time to screw with software instead of actually going sailing. Can't say this is an improvement on life in general.

FKT

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On 7/28/2021 at 7:33 PM, NaClH20 said:

My (admittedly, limited) experience with Garmin is that they will support their products for a generation or two and then drop them for the latest and greatest.  Perhaps that is no longer the case; I don’t know.  I was soured on them once and thus will no longer consider their products (listening, Garmin??   And everyone else?).   I have Furuno equipment dating to 1996 that still works and still gets factory support, so anything new will come from them or a similar company.  I’ll spend the extra boat bucks for that, thank you.

 

I have been on the road with limited coherence, so I waited until home for this.

GARMIN SUPPORT SUCKS.

I bought a GPSMap 276CX to replace my ancient 276C. Apart from the screen size, it is in every way inferior to the older unit. Slower redraw, limited feature set, shitty manual. The map update feature never did work.

I contacted them in the past regarding mapping layers being in the wrong order, features dropping out on zoom, etc. I got a nice email back explaining that the maps were in layers and totally missing the point of what I was saying.

The last time I contacted them, I was trying to get the tidal current graphs to be normal, like

406329621_KelletBluff.thumb.JPG.d0e0422bd128511bc2516a44681954e4.JPG

instead of

1762303140_ActivePass.thumb.JPG.c25549b1a0101cf4913c45c1f1eae42c.JPG

Obviously the bottom one is as useful as tits on a pencil. The person who answered me said that it was because the Canadian data was in a different format, so I sent him a screenshot of a Canadian location between these two spots that looked normal.

He answered that they were aware of it and had no intention of fixing it, and besides I could use them as is with a little interpolation. I thought I did well in not telling him to shove his desk up his ass.

FUCK GARMIN.

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I've begrudgingly stuck with navionics because I haven't found anything better as far as matching the bottom contours using their sonar chart display, at least in the Chesapeake.  Not wild about the interface of navionics tho..  but earlier this year we went into Queenstown creek at about 11pm on a moonless night.  Only about 1.5 feet under my keel coming in there at the shallow spots, but the depth contours seemed very accurate.  Tight channel, especially at night.

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Just now, bgytr said:

I've begrudgingly stuck with navionics because I haven't found anything better as far as matching the bottom contours using their sonar chart display, at least in the Chesapeake.  Not wild about the interface of navionics tho..  but earlier this year we went into Queenstown creek at about 11pm on a moonless night.  Only about 1.5 feet under my keel coming in there at the shallow spots, but the depth contours seemed very accurate.  Tight channel, especially at night.

That channel frequently involves hitting bottom, moving over 10 feet, and trying again. I would say Navionics did well with that. I always wondered how they deal with the tide and miscalculated offsets when adding the user data to the depth contours.

 

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11 hours ago, Ishmael said:

I have been on the road with limited coherence, so I waited until home for this.

GARMIN SUPPORT SUCKS.

I bought a GPSMap 276CX to replace my ancient 276C. Apart from the screen size, it is in every way inferior to the older unit. Slower redraw, limited feature set, shitty manual. The map update feature never did work.

I contacted them in the past regarding mapping layers being in the wrong order, features dropping out on zoom, etc. I got a nice email back explaining that the maps were in layers and totally missing the point of what I was saying.

The last time I contacted them, I was trying to get the tidal current graphs to be normal, like

406329621_KelletBluff.thumb.JPG.d0e0422bd128511bc2516a44681954e4.JPG

instead of

1762303140_ActivePass.thumb.JPG.c25549b1a0101cf4913c45c1f1eae42c.JPG

Obviously the bottom one is as useful as tits on a pencil. The person who answered me said that it was because the Canadian data was in a different format, so I sent him a screenshot of a Canadian location between these two spots that looked normal.

He answered that they were aware of it and had no intention of fixing it, and besides I could use them as is with a little interpolation. I thought I did well in not telling him to shove his desk up his ass.

FUCK GARMIN.

The engineer who dropped a rectifier bridge in the tide algorithm is called to the helpdesk...

Joke aside, the negative current in the first shot would have confused me as for me a tidal current is a speed (thus positive) and a direction, if you give negative speed you then need to invert the heading.... Actually the first image is probably wrong as -2.1kt at 154º is +2.1kt @ 334º which roughly in the same direction as 344º and i doubt that the tidal current keeps going roughly in the same direction...

So IMHO, it is a bugfix rather than a new bug...

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1 hour ago, kent_island_sailor said:

That channel frequently involves hitting bottom, moving over 10 feet, and trying again. I would say Navionics did well with that. I always wondered how they deal with the tide and miscalculated offsets when adding the user data to the depth contours.

 

My guess is that they have the time and the measured depth and recalculate the tide height or better take it from a tide gauge. Nevertheless many boats have an offset that is wrong (ie from the bottom of the keel plus some extra...) and I wonder how they deal with that. I hate the random offsets as this ends up very confusing when you are anchoring, I prefer to have the real height and when I see 2m, I know that the tack is already overdue if I have 1.8m draft :D :rolleyes:

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10 hours ago, Panoramix said:

My guess is that they have the time and the measured depth and recalculate the tide height or better take it from a tide gauge. Nevertheless many boats have an offset that is wrong (ie from the bottom of the keel plus some extra...) and I wonder how they deal with that. I hate the random offsets as this ends up very confusing when you are anchoring, I prefer to have the real height and when I see 2m, I know that the tack is already overdue if I have 1.8m draft :D :rolleyes:

I have my depth plotter display depth under the transducer. That's the number that's important to me. And I don't want to have to explain to my GF that she needs to do some mental subtraction to keep from running aground.

Now for uploading data then IMHO you need 4 values - date/time at UTC 0, lat/long and depth from surface. Then people can make corrections for state of tide where you took the recordings.

FKT

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1 hour ago, Fah Kiew Tu said:

I have my depth plotter display depth under the transducer. That's the number that's important to me. And I don't want to have to explain to my GF that she needs to do some mental subtraction to keep from running aground.

Now for uploading data then IMHO you need 4 values - date/time at UTC 0, lat/long and depth from surface. Then people can make corrections for state of tide where you took the recordings.

FKT

In the Chesapeake the tide tables are like the pirate code - more like guidelines. Sustained winds can have the actual water depth way the hell off the predictions.

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26 minutes ago, kent_island_sailor said:

In the Chesapeake the tide tables are like the pirate code - more like guidelines. Sustained winds can have the actual water depth way the hell off the predictions.

Yeah that would make life a lot more interesting. Haven't had to cope with that where I live. Only about a metre or so of tide range.

FKT

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8 hours ago, Fah Kiew Tu said:

Yeah that would make life a lot more interesting. Haven't had to cope with that where I live. Only about a metre or so of tide range.

FKT

Here one metre can be about 20 minutes of tide going up or down... 

I respect other people way of doing things but I don't like depth below transducer either, it just creates another offset you have to get right when you decide where to anchor. If you have your offset at water level, the reading you get is "how much water there is where I am", which is convenient as it translates directly to what you read on the map. Say you decide you need to drop anchor at 2m above datum and the tide right now is at 6.5 -> 6.5-2 = 4.5, easy you are in the right spot when you read 4.5 on the depth sounder. If you have no offset and thus are at transducer depth (say 0.3) it becomes 6.5-2-0.3 = 4.2 - not high level maths but an extra opportunity to get it wrong. When you use the sounder to decide when it it is time to tack, you just set a target which will depend anyway of the sea state and the nature of the bottom such as "tack at 3m" in breezy conditions, "tack at 2m" in drifting conditions in a sheltered bay or even "tack at 15m" in gale conditions. If you have an offset not at water level, you will need to factor it in these cases.

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2 minutes ago, Panoramix said:

Here one metre can be about 20 minutes of tide going up or down... 

I respect other people way of doing things but I don't like depth below transducer either, it just creates another offset you have to get right when you decide where to anchor. If you have your offset at water level, the reading you get is "how much water there is where I am", which is convenient as it translates directly to what you read on the map. Say you decide you need to drop anchor at 2m above datum and the tide right now is at 6.5 -> 6.5-2 = 4.5, easy you are in the right spot when you read 4.5 on the depth sounder. If you have no offset and thus are at transducer depth (say 0.3) it becomes 6.5-2-0.3 = 4.2 - not high level maths but an extra opportunity to get it wrong. When you use the sounder to decide when it it is time to tack, you just set a target which will depend anyway of the sea state and the nature of the bottom such as "tack at 3m" in breezy conditions, "tack at 2m" in drifting conditions in a sheltered bay or even "tack at 15m" in gale conditions. If you have an offset not at water level, you will need to factor it in these cases.

I'd like to see you explain that to my GF.... she is a very bright woman, couple of university degrees, at least 3 postgrad diplomas, but that sort of mental arithmetic would not go well.

Lot easier to say 'watch the sounder, tell me when we've gotten to 3m depth'.

FKT

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28 minutes ago, Fah Kiew Tu said:

I'd like to see you explain that to my GF.... she is a very bright woman, couple of university degrees, at least 3 postgrad diplomas, but that sort of mental arithmetic would not go well.

Lot easier to say 'watch the sounder, tell me when we've gotten to 3m depth'.

FKT

Tack at 3m is basically the same as watch the sounder and tack when we get to 3m...

In tidal areas I can't see a way to avoid adding / substracting water height and the sounding on the map... Where I sail if you don't, depending on time you can get it wrong by 14m (map Datum is about 14m below the highest tide...)

It isn't rocket science, they used to teach that to people who had left school aged 14....

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1 hour ago, Panoramix said:

When you use the sounder to decide when it it is time to tack, you just set a target which will depend anyway of the sea state and the nature of the bottom such as "tack at 3m" in breezy conditions, "tack at 2m" in drifting conditions

  We used to do a passage race in a 26' er.  We set the sounder alarm at 10' to tack.Sometimes we still touched bottom and lost places. 

One year the sounder stopped working before the start of the race so we had to use observation and judgement instead.  Didn't touch bottom once and finished better than we did the years before.

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4 hours ago, Panoramix said:

Tack at 3m is basically the same as watch the sounder and tack when we get to 3m...

In tidal areas I can't see a way to avoid adding / substracting water height and the sounding on the map... Where I sail if you don't, depending on time you can get it wrong by 14m (map Datum is about 14m below the highest tide...)

It isn't rocket science, they used to teach that to people who had left school aged 14....

3 ways I have seem them set:

1. Actual depth

2. Depth below the keel

3. Random, no offset applied and maybe someone knows the correction.

I like #1, seeing 6 feet means it is 6 feet deep ;)

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I like #2. The main reason I'm looking at depth is to determine if I'm going to hit and I don't want to be doing arithmetic in my head during a dodgy approach. Zero = No Bueno is pretty easy to remember.

Secondarily it's to figure out anchoring scope but since that requires correction factors for bow roller height and tide cycle anyway, it's no big deal to add a 6' depth correction for the calibration of the sounder.

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7 hours ago, IStream said:

I like #2. The main reason I'm looking at depth is to determine if I'm going to hit and I don't want to be doing arithmetic in my head during a dodgy approach. Zero = No Bueno is pretty easy to remember.

This. That number is the only one I actually care about, for exactly the reason you say. It's dead easy to explain to my GF, if we're under 1m, stop.

"In tidal areas I can't see a way to avoid adding / substracting water height and the sounding on the map... Where I sail if you don't, depending on time you can get it wrong by 14m (map Datum is about 14m below the highest tide...) "

I don't understand the meaning of this. My interpretation is, Pano is saying that the depth recorded on the bathy chart/map is what you should be using when deciding when to tack. I don't do that at all, I use the ACTUAL depth under the transducer. The map depth is more like a bit of advice of what to expect rather than anything definitive. And when I was a lot younger, I spent considerable time at sea doing fisheries survey work in northern Australia with 10m tides. We only ran aground accidentally once.

FKT

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13 hours ago, IStream said:

I like #2. The main reason I'm looking at depth is to determine if I'm going to hit and I don't want to be doing arithmetic in my head during a dodgy approach. Zero = No Bueno is pretty easy to remember.

Secondarily it's to figure out anchoring scope but since that requires correction factors for bow roller height and tide cycle anyway, it's no big deal to add a 6' depth correction for the calibration of the sounder.

In real life the "No bueno" area will never be 0m. It might be 0.2m in glassy conditions or 10m in bad weather conditions so you aren't really saving yourself any hassle... It is just a different set of numbers which are mine offset by the boat draft.

Obviously there are many ways to do most things, what really matters is not hitting the ground.. . 

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16 hours ago, Fah Kiew Tu said:

This. That number is the only one I actually care about, for exactly the reason you say. It's dead easy to explain to my GF, if we're under 1m, stop.

"In tidal areas I can't see a way to avoid adding / substracting water height and the sounding on the map... Where I sail if you don't, depending on time you can get it wrong by 14m (map Datum is about 14m below the highest tide...) "

I don't understand the meaning of this. My interpretation is, Pano is saying that the depth recorded on the bathy chart/map is what you should be using when deciding when to tack. I don't do that at all, I use the ACTUAL depth under the transducer. The map depth is more like a bit of advice of what to expect rather than anything definitive. And when I was a lot younger, I spent considerable time at sea doing fisheries survey work in northern Australia with 10m tides. We only ran aground accidentally once.

FKT

If you want more than 1 meter under the keel, there are a TON of places in the Chesapeake you would go no place near. I am happy some places with an inch or two and sometimes wake up aground at low tide. Of course this is soft mud, in places with rock or coral 1 meter it is!

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