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Old 14-01-2015, 07:50   #286
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pirate Re: Another foundering how do chart plotters get it wrong

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Originally Posted by FamilyVan View Post
When I worked Search and Rescue in the Coast Guard we found paper charts to be a challenge on our Hurricanes. We would photocopy and laminate 8.5x11 sections so we could put it in a binder. We used dry erase markers on the laminate.

At the time we had early monochrome Chartplotters on the Hurricanes. But having something portable you could take with you was just so handy. For example, if you had to board a stricken yacht you could have the plotter on the Hurricane and take the binder with you on the yacht- or ashore (for a shoreline search).
They were also handy for investigating- you could take it say to a relative's home and say- can you point to your sons favourite fishing hole.

I'm not sure of the legal issues surrounding this practice as the CCG and the Canadian Hydrographic Service were more or less the same entity.

For a cruiser this might be useful for taking charts in your dinghy, ashore, or to take to another boat or bar or something to ask locals about certain chart features.

But again, I don't have enough knowledge of copy right laws to comment on the legality of this.

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One of the advantages of living in the Free World...
To be honest if your not profiting.. ie selling the copies.. your good to go in my mind.. keep your original safe and updated.
Its like buying the Wharram plans for a Tiki.. if I copy and sell em on.. illegal.
If I copy them so they don't get wrecked in the w/shop.. legal.
But then... I'm just a Fool..
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Old 14-01-2015, 07:51   #287
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Re: Another foundering how do chart plotters get it wrong

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Originally Posted by FamilyVan View Post
For a cruiser this might be useful for taking charts in your dinghy, ashore, or to take to another boat or bar or something to ask locals about certain chart features.
I do this all the time with my iPad (in a waterproof case). I also use it in poorly charted areas that we anchor in to go around in the dinghy and mark up uncharted/inaccurate reefs, unmarked safe channels and passages, etc on the main electronic chart. If I find a good fishing reef, that gets marked too. Very useful.

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Old 14-01-2015, 08:06   #288
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Re: Another foundering how do chart plotters get it wrong

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I do this all the time with my iPad (in a waterproof case). I also use it in poorly charted areas that we anchor in to go around in the dinghy and mark up uncharted/inaccurate reefs, unmarked safe channels and passages, etc on the main electronic chart. If I find a good fishing reef, that gets marked too. Very useful.

Mark
Ya, I could see a tablet being useful in that situation. Tablet- or even smart phone technology didn't exist in the time frame I'm talking about.

I don't know if they still carry those little binders on the Hurricanes any more. I'm guessing the guys probably use their Smartphones for a lot of that stuff now. I'm not sure how well a tablet would stand up to a 40 knot ride in choppy seas.

Same principle either way though.

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Old 14-01-2015, 08:19   #289
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pirate Re: Another foundering how do chart plotters get it wrong

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Originally Posted by colemj View Post
I do this all the time with my iPad (in a waterproof case). I also use it in poorly charted areas that we anchor in to go around in the dinghy and mark up uncharted/inaccurate reefs, unmarked safe channels and passages, etc on the main electronic chart. If I find a good fishing reef, that gets marked too. Very useful.

Mark
Had to do similar on my last trip.. my Laptop died so took a picture of a locals chart with my android and used it to navigate down to Eemshaven.. love the TP expand thingy..
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Old 14-01-2015, 08:42   #290
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Re: Another foundering how do chart plotters get it wrong

Off topic.....Boatman r u still "in the Sun" over there.......


Life is good if you Keepa Smilin......





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Old 14-01-2015, 08:49   #291
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Re: Another foundering how do chart plotters get it wrong

This may be old news to many but you can get paper charts from NOAA in PDF format. Then you can print your own if you have large enough printer.

NOAA Charts PDF Format

Also, for some regions they have a nice booklet PDF format too:

BookletChart™

I wish all countries would publish like NOAA does. It's a shame such important safety information isn't freely available to the people that have already paid for it through their taxes.
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Old 14-01-2015, 09:50   #292
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Re: Another foundering how do chart plotters get it wrong

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Seems like that opens up an entirely different can of worms. Intellectual property and all that, you know.

Not to mention, if people think others get into problems now simply using chartplotters - then developing software techniques to crack file encryption, properly orientate and display a chart and print it on a suitable large-format printer on quality paper seems like a stretch to me. And an expensive one at that.

You aren't actually suggesting that this is the future?

Mark
Up to date Electronic versions of EVERY paper chart for the Mediterranean costs about $300 from CMAP for my Nav/Planning laptop in the Saloon.
Another $300 for the equivalent Garmin charts for the entire Mediterranean for my Garmin CP.
Each navigation system using their own GPS receivers are a cross check.
The Nav Laptop is the absolute winner for passage planning.
Zoom in to the MAX and mark all the hard, sharp bits as red waypoints as a reminder.
Paper charts just can't compete.
Coupled with integrated AIS and occasional use of Radar all the information is at my fingertips ........updating continually and leaving a track.
My primary navigation tool is being on deck looking...looking...looking.
Works for me.
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Old 14-01-2015, 11:27   #293
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Re: Another foundering how do chart plotters get it wrong

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Well, then you have circled us right back around on this topic. When paper charts are no longer even available (as is actually happening now in some areas), how will people be drawing in pencil bearings and calculating drift and plotting positions, etc?
On old, 'outdated' charts, perhaps? :-)

I just don't see paper charts 'disappearing' any time soon... I think most Hydrographic Services around the world will retain the ability to have Print-On-Demand charts available well into the future, and I think there will still be at least some demand for paper charts in the form of the popular chart folios/chartbooks for well-frequented cruising grounds like those from Maptech, and the Explorer Chartbooks... I could be wrong, of course, but I'll be too long departed from this world for it to matter much... :-)

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Originally Posted by colemj View Post
Seems like those who are regularly castigated for not having paper charts and relying on chartplotters and electronic tools for primary navigation are just ahead of the curve.

Mark
Maybe... But surely you know by now, my approach on this sort of stuff will never be remotely confused with being 'cutting edge', or 'ahead of the curve'... My Greatest Claim to Fame, after all, may likely be as the last motorsports photographer to have ever shot an F1 or Indy Car race on Film...

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Old 14-01-2015, 13:52   #294
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Re: Another foundering how do chart plotters get it wrong

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Originally Posted by Jon Eisberg View Post
I just don't see paper charts 'disappearing' any time soon... I think most Hydrographic Services around the world will retain the ability to have Print-On-Demand charts available well into the future, and I think there will still be at least some demand for paper charts in the form of the popular chart folios/chartbooks for well-frequented cruising grounds like those from Maptech, and the Explorer Chartbooks... I could be wrong, of course, but I'll be too long departed from this world for it to matter much... :-)
It will be interesting to see how this all develops. No doubt major Hydrographic Services will retain POD for now, and maybe into the future. But who is going to draw new raster charts, and not just update existing ones? And when charting programs start to take advantage of survey data in new and better ways (satellite overlay, HD soundings, etc), will these types of data make it into raster charts, or will the new data collection methods even be ones that can be turned into a raster chart?

Then there is the competition of not only private companies doing their own surveying now, but of crowd-sourced surveying that is gaining steam quickly. It is unlikely any of these data will ever be produced in paper form.

Finally, there is cost of surveying itself. If private and crowd-sourcing starts competing hard, the cost/value of government programs may be politically fragile.

When the Antarctic opens up as a popular cruising ground, I bet the only charts you will be able to find will be electronic!

You might live long enough to have two Greatest Claims To Fame yet…

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Old 14-01-2015, 15:34   #295
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Re: Another foundering how do chart plotters get it wrong

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The Nav Laptop is the absolute winner for passage planning.
Zoom in to the MAX and mark all the hard, sharp bits as red waypoints as a reminder.
Paper charts just can't compete.
Here's where I disagree... Not saying you're 'Wrong' about this, each of us is 'wired' differently, of course. But for me, there is a big limitation imposed upon ECS for 'Big Picture'/Initial planning purposes, by the basic restriction of the number of pixels that comprise what's being seen on the screen. To my eye, a computer/tablet/chartplotter screen "just can't compete" with the amount of information displayed with such clarity AT A GLANCE on a full size paper chart spread out before me...

What follows will be a long-winded attempt to illustrate by example what i mean :-)

I do much of my sailing singlehanded, so factoring in the minimization of making a navigational error due to fatigue or distraction is important to me. At the start of my cruise last summer, I sailed direct from Nantucket out to St Peter's on Cape Breton Island, an even 500 miles... It was a sporty, fast ride in the wake of the passage of Hurricane Arthur, but the last 300 miles were in very heavy fog, with a radar that went tits up abeam of Halifax... So, by the time I was abeam of Cape Canso, and ready to make the turn inshore towards the Canso Ledges and the entrance to Chedabucto Bay, I was pretty tired, and quite possibly prone to making a mistake, or overlooking something important...

From a safe distance off Cape Canso, it's a straight shot of about 15 miles or so across Chedabucto Bay up towards the top of Isle Madame. Navigation is pretty straightforward, the main concern is the shipping lanes leading towards the Strait of Canso... As soon as I knew I had cleared the danger of the ledges off Cape Canso, I used my iPad to shoot a waypoint up to the next turning mark off Isle Madame. Right at that point, it was time to switch from one paper chart to the next, so I jumped down below to unfold the next chart, to confirm what I'd plotted on the iPad. Normally, I'd refer to the chart first, then plot the waypoint electronically, but I knew in this instance I had a bit of wiggle room, no dangers immediately ahead, at any rate...

Here's the next chart, the Strait of Canso and Approaches. The scale of this chart is 1:75,000… My next leg would run from E of the Canso Ledges at the bottom right, on a course of 0 degrees True just a bit to the left of the compass rose near the right side of the chart:





I'd been thru there a few years before, and I had a vague recollection of something that seemed to be 'missing' from my initial view on the iPad... Sure enough, clear as day AT MY FIRST LOOK at the paper chart, my memory was refreshed... On the opposite side of the Chedabucto Traffic Separation Zones, precisely on my track midway up to the waypoint I'd plotted, was the indication of a lighted bell buoy, adjacent to a feature called "ORPHEUS ROCK"... Although not clearly visible in the pic posted above, you can see something indicated just to the left of the compass rose. Trust me, with this chart spread out before you, even the most cursory scan of that route, it jumps right out at you, one would have to be catatonic with exhaustion to miss it… :-)

Needless to say, anything named a "Rock" in Atlantic Canada deserves your attention :-) Turns out Orpheus Rock is a major hazard, awash at low water, and breaks heavily if there's a sea running. I saw this firsthand on my return 6 weeks later, when I re-crossed the bay with a heavy swell running in from a tropical storm passing well off to the east...

Now, here is the full-screen view of "Orpheus Rock" on the iPad, when viewed at the same 1:75,000 scale as the paper chart… In my opinion, I'd say it's the electronic display "that can't compete" with that 28" X 44" sheet of paper, in terms of the clarity and sheer wealth of information provided, at the equivalent scale… :-)

Orpheus Rock is represented by that green blob in the center of the screen - but nothing more:




As you see, nothing distinct or 'alarming' is yet indicated, I had to zoom in considerably even before the existence of the lighted nav aid is revealed. And, I had to zoom into a scale of 1:12,000 before the notation "Orpheus Rock" appears... And yet, even at the maximum zoom range, no "+" or "*" markings indicating a ROCK that is awash at low water or in a heavy swell , whereas those notations are clearly shown on the paper chart at a scale of 1:75K...

Again, for a tired navigator who might not be thinking, or seeing as clearly as he should, seems to me this sort of discrepancy could make all the difference in the world, and I think having a paper chart gives me that extra insurance against the possibility of overlooking, or missing something critical..

Now, much is made of the ability to 'Fly the Route' with ECS at a greater level of zoom… Well, I think we've been reminded of the potential fallibility of that approach, with what likely happened with TEAM VESTAS WIND… Moreover, that method strikes me as being better suited to the drivers of Sea Rays, who configure routes that are closely adhered to by the interfacing of an autopilot to the waypoints in a plotter… But for SAILORS, or at least some of us, rarely showing a Cross-Track Error of more than a boat width or two, might tend to be the exception, rather than the rule, and it's not hard to picture how easily we might deviate from the route previously 'flown' at a level sufficient to reveal any and all dangers that might be encountered…

Just one dinosaur's opinion, as always...

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Old 14-01-2015, 15:45   #296
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Re: Another foundering how do chart plotters get it wrong

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Just one dinosaur's opinion, as always...

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My experience also.

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Old 14-01-2015, 16:37   #297
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Re: Another foundering how do chart plotters get it wrong

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Originally Posted by Jon Eisberg View Post
Now, much is made of the ability to 'Fly the Route' with ECS at a greater level of zoom… Well, I think we've been reminded of the potential fallibility of that approach, with what likely happened with TEAM VESTAS WIND… Moreover, that method strikes me as being better suited to the drivers of Sea Rays, who configure routes that are closely adhered to by the interfacing of an autopilot to the waypoints in a plotter… But for SAILORS, or at least some of us, rarely showing a Cross-Track Error of more than a boat width or two, might tend to be the exception, rather than the rule, and it's not hard to picture how easily we might deviate from the route previously 'flown' at a level sufficient to reveal any and all dangers that might be encountered…
OK, I think you went off the rails here Jon. I realize you don't have much experience with electronic charting, and prefer to think that people who do use them to full extent, as well as be able to stay on a small XTE route, are not real sailors, but - really?

First, have you ever used a charting program that will run a route and list obstacles found? You write like you don't have much experience, because you have made some mistaken assumptions about this feature. You might not realize that these programs do a lot more than just point out only features that a route line crosses over. And that they update this list depending on your actual track - regardless of it deviating from your route.

What do you have against a charting program that does provide a list of potential hazards and/or obstacles when you plot a route and updates it based on your actual track? Why are those of us who use these tools "SeaRay drivers"?

What is wrong with allowing one's autopilot to compensate for current or leeway so that a large cross-track error is not produced and one doesn't find themselves unexpectedly off course? Again, why the derisive analogy to "SeaRay drivers"? BTW, your windvane slavishly follows the wind - this is far more dangerous than compensating for set and drift. But it does solidly place you in the "non-SeaRay" category, which seems to be important to you.

You imply that some of these tools were used by Vestas, but you have no proof of that. If you are saying that they didn't use these tools, then your point is silly and cheap.

I was with you up until this last paragraph - which seems to imply more about you personally than about navigation.

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Old 14-01-2015, 16:53   #298
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Re: Another foundering how do chart plotters get it wrong

Jon,

Maybe it's the electronic chart you are using. This is what OpenCPN shows on a CM-93 chart of that area. Is that your rock with a big bullseye in the middle of the chart at scale 450,000?
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Old 14-01-2015, 16:56   #299
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Re: Another foundering how do chart plotters get it wrong

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Originally Posted by Jon Eisberg View Post
Here's where I disagree... Not saying you're 'Wrong' about this, each of us is 'wired' differently, of course. But for me, there is a big limitation imposed upon ECS for 'Big Picture'/Initial planning purposes, by the basic restriction of the number of pixels that comprise what's being seen on the screen. To my eye, a computer/tablet/chartplotter screen "just can't compete" with the amount of information displayed with such clarity AT A GLANCE on a full size paper chart spread out before me...

What follows will be a long-winded attempt to illustrate by example what i mean :-)

I do much of my sailing singlehanded, so factoring in the minimization of making a navigational error due to fatigue or distraction is important to me. At the start of my cruise last summer, I sailed direct from Nantucket out to St Peter's on Cape Breton Island, an even 500 miles... It was a sporty, fast ride in the wake of the passage of Hurricane Arthur, but the last 300 miles were in very heavy fog, with a radar that went tits up abeam of Halifax... So, by the time I was abeam of Cape Canso, and ready to make the turn inshore towards the Canso Ledges and the entrance to Chedabucto Bay, I was pretty tired, and quite possibly prone to making a mistake, or overlooking something important...

From a safe distance off Cape Canso, it's a straight shot of about 15 miles or so across Chedabucto Bay up towards the top of Isle Madame. Navigation is pretty straightforward, the main concern is the shipping lanes leading towards the Strait of Canso... As soon as I knew I had cleared the danger of the ledges off Cape Canso, I used my iPad to shoot a waypoint up to the next turning mark off Isle Madame. Right at that point, it was time to switch from one paper chart to the next, so I jumped down below to unfold the next chart, to confirm what I'd plotted on the iPad. Normally, I'd refer to the chart first, then plot the waypoint electronically, but I knew in this instance I had a bit of wiggle room, no dangers immediately ahead, at any rate...

Here's the next chart, the Strait of Canso and Approaches. The scale of this chart is 1:75,000… My next leg would run from E of the Canso Ledges at the bottom right, on a course of 0 degrees True just a bit to the left of the compass rose near the right side of the chart:





I'd been thru there a few years before, and I had a vague recollection of something that seemed to be 'missing' from my initial view on the iPad... Sure enough, clear as day AT MY FIRST LOOK at the paper chart, my memory was refreshed... On the opposite side of the Chedabucto Traffic Separation Zones, precisely on my track midway up to the waypoint I'd plotted, was the indication of a lighted bell buoy, adjacent to a feature called "ORPHEUS ROCK"... Although not clearly visible in the pic posted above, you can see something indicated just to the left of the compass rose. Trust me, with this chart spread out before you, even the most cursory scan of that route, it jumps right out at you, one would have to be catatonic with exhaustion to miss it… :-)

Needless to say, anything named a "Rock" in Atlantic Canada deserves your attention :-) Turns out Orpheus Rock is a major hazard, awash at low water, and breaks heavily if there's a sea running. I saw this firsthand on my return 6 weeks later, when I re-crossed the bay with a heavy swell running in from a tropical storm passing well off to the east...

Now, here is the full-screen view of "Orpheus Rock" on the iPad, when viewed at the same 1:75,000 scale as the paper chart… In my opinion, I'd say it's the electronic display "that can't compete" with that 28" X 44" sheet of paper, in terms of the clarity and sheer wealth of information provided, at the equivalent scale… :-)

Orpheus Rock is represented by that green blob in the center of the screen - but nothing more:




As you see, nothing distinct or 'alarming' is yet indicated, I had to zoom in considerably even before the existence of the lighted nav aid is revealed. And, I had to zoom into a scale of 1:12,000 before the notation "Orpheus Rock" appears... And yet, even at the maximum zoom range, no "+" or "*" markings indicating a ROCK that is awash at low water or in a heavy swell , whereas those notations are clearly shown on the paper chart at a scale of 1:75K...

Again, for a tired navigator who might not be thinking, or seeing as clearly as he should, seems to me this sort of discrepancy could make all the difference in the world, and I think having a paper chart gives me that extra insurance against the possibility of overlooking, or missing something critical..

Now, much is made of the ability to 'Fly the Route' with ECS at a greater level of zoom… Well, I think we've been reminded of the potential fallibility of that approach, with what likely happened with TEAM VESTAS WIND… Moreover, that method strikes me as being better suited to the drivers of Sea Rays, who configure routes that are closely adhered to by the interfacing of an autopilot to the waypoints in a plotter… But for SAILORS, or at least some of us, rarely showing a Cross-Track Error of more than a boat width or two, might tend to be the exception, rather than the rule, and it's not hard to picture how easily we might deviate from the route previously 'flown' at a level sufficient to reveal any and all dangers that might be encountered…

Just one dinosaur's opinion, as always...

:-))
I've navigated the East Coast of Cape Breton. I agree, it is not a good place to be without Paper Charts.
I studied for a while at the Coast Guard College. Not far up the coast from there.

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Old 15-01-2015, 02:10   #300
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Re: Another foundering how do chart plotters get it wrong

Quote:
Originally Posted by Jon Eisberg View Post
Here's where I disagree... Not saying you're 'Wrong' about this, each of us is 'wired' differently, of course. But for me, there is a big limitation imposed upon ECS for 'Big Picture'/Initial planning purposes, by the basic restriction of the number of pixels that comprise what's being seen on the screen. To my eye, a computer/tablet/chartplotter screen "just can't compete" with the amount of information displayed with such clarity AT A GLANCE on a full size paper chart spread out before me...

What follows will be a long-winded attempt to illustrate by example what i mean :-)

I do much of my sailing singlehanded, so factoring in the minimization of making a navigational error due to fatigue or distraction is important to me. At the start of my cruise last summer, I sailed direct from Nantucket out to St Peter's on Cape Breton Island, an even 500 miles... It was a sporty, fast ride in the wake of the passage of Hurricane Arthur, but the last 300 miles were in very heavy fog, with a radar that went tits up abeam of Halifax... So, by the time I was abeam of Cape Canso, and ready to make the turn inshore towards the Canso Ledges and the entrance to Chedabucto Bay, I was pretty tired, and quite possibly prone to making a mistake, or overlooking something important...

From a safe distance off Cape Canso, it's a straight shot of about 15 miles or so across Chedabucto Bay up towards the top of Isle Madame. Navigation is pretty straightforward, the main concern is the shipping lanes leading towards the Strait of Canso... As soon as I knew I had cleared the danger of the ledges off Cape Canso, I used my iPad to shoot a waypoint up to the next turning mark off Isle Madame. Right at that point, it was time to switch from one paper chart to the next, so I jumped down below to unfold the next chart, to confirm what I'd plotted on the iPad. Normally, I'd refer to the chart first, then plot the waypoint electronically, but I knew in this instance I had a bit of wiggle room, no dangers immediately ahead, at any rate...

Here's the next chart, the Strait of Canso and Approaches. The scale of this chart is 1:75,000… My next leg would run from E of the Canso Ledges at the bottom right, on a course of 0 degrees True just a bit to the left of the compass rose near the right side of the chart:





I'd been thru there a few years before, and I had a vague recollection of something that seemed to be 'missing' from my initial view on the iPad... Sure enough, clear as day AT MY FIRST LOOK at the paper chart, my memory was refreshed... On the opposite side of the Chedabucto Traffic Separation Zones, precisely on my track midway up to the waypoint I'd plotted, was the indication of a lighted bell buoy, adjacent to a feature called "ORPHEUS ROCK"... Although not clearly visible in the pic posted above, you can see something indicated just to the left of the compass rose. Trust me, with this chart spread out before you, even the most cursory scan of that route, it jumps right out at you, one would have to be catatonic with exhaustion to miss it… :-)

Needless to say, anything named a "Rock" in Atlantic Canada deserves your attention :-) Turns out Orpheus Rock is a major hazard, awash at low water, and breaks heavily if there's a sea running. I saw this firsthand on my return 6 weeks later, when I re-crossed the bay with a heavy swell running in from a tropical storm passing well off to the east...

Now, here is the full-screen view of "Orpheus Rock" on the iPad, when viewed at the same 1:75,000 scale as the paper chart… In my opinion, I'd say it's the electronic display "that can't compete" with that 28" X 44" sheet of paper, in terms of the clarity and sheer wealth of information provided, at the equivalent scale… :-)

Orpheus Rock is represented by that green blob in the center of the screen - but nothing more:




As you see, nothing distinct or 'alarming' is yet indicated, I had to zoom in considerably even before the existence of the lighted nav aid is revealed. And, I had to zoom into a scale of 1:12,000 before the notation "Orpheus Rock" appears... And yet, even at the maximum zoom range, no "+" or "*" markings indicating a ROCK that is awash at low water or in a heavy swell , whereas those notations are clearly shown on the paper chart at a scale of 1:75K...

Again, for a tired navigator who might not be thinking, or seeing as clearly as he should, seems to me this sort of discrepancy could make all the difference in the world, and I think having a paper chart gives me that extra insurance against the possibility of overlooking, or missing something critical..

Now, much is made of the ability to 'Fly the Route' with ECS at a greater level of zoom… Well, I think we've been reminded of the potential fallibility of that approach, with what likely happened with TEAM VESTAS WIND… Moreover, that method strikes me as being better suited to the drivers of Sea Rays, who configure routes that are closely adhered to by the interfacing of an autopilot to the waypoints in a plotter… But for SAILORS, or at least some of us, rarely showing a Cross-Track Error of more than a boat width or two, might tend to be the exception, rather than the rule, and it's not hard to picture how easily we might deviate from the route previously 'flown' at a level sufficient to reveal any and all dangers that might be encountered…

Just one dinosaur's opinion, as always...

:-))
The "green blob" should be more than enough of a hint telling you to zoom in and look more closely and if there is any doubt, avoid.

These are screen shots from the Navionics web app which is what you will see on a MFD using Navionics and on their iPad app.

The only way you would not see Orpheus Rock as a navigation hazard to avoid would be if you don't open your eyes. Call me suspicious but when sailing, but I would also avoid the shallows to the west as well even if it didn't have the "R" (is that a rock?) even though it appears more than deep enough.
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