Are NOAA ENC charts really this crappy?

[emilecantin]

For context: I've been using the awesome Canadian ENC charts from o-charts since they came out; and I never understood why would anyone prefer raster charts over vector ones.

I'm now in the US, cruising down the east coast, so naturally I used the chart downloader to download the relevant ENC charts.

I don't know if I'm doing something wrong, but these charts are pretty weird; often I'd zoom OUT and a buoy would appear, then I zoom IN and it disappears... However this week it got much worse: after coming in to New London, a fellow sailor came to warn me about an underwater rock near the entrance to the marina, he saw me coming in and apparently I had passed pretty close.

Looking at Navionics on my phone, indeed it's well-marked, same with the NOAA Raster charts. However, it's completely absent from the ENC charts!

Here is the RNC chart (showing how close I came to that rock!):


And here is the ENC chart:


Anyone else noticed this?

[SV_Galateia]

The information is there. It's a settings issue. You have to adjust the settings for what you want to see and what you do not want to see to minimize screen clutter

With that said, you would think that something like an underwater hazard would be something you had to knowingly turn off...not something that you had to think/know to turn on...

[wholybee]

Agreed, it is a settings issue. It is a PITA. In chart settings there is a checkbox "reduce detail at small scale." I would start with that. If that doesn't do it, try changing the display category to show everything. Undoubtably, that will clutter the display with too much detail, but you can then uncheck what you don't want/need and go from there.

I don't think it works with NOAA charts, but you can also try pressing "D" for detail and adjusting the detail level.

[PippaB]

Definitely a settings thing, the official online NOAA ENC Viewer shows it quite clearly about the same zoom level with default settings, so the data is clearly present. Don’t know why that would be part of a de-clutter option, clearly dangerous if it is.

[requiem]

I just loaded that ENC onto both OpenCPN and SEAiq, and hogback showed on both. I also had the "reduce detail at small scale" enabled, but that shouldn't affect this.

If you click the "reset to standard" button the rock symbol will disappear. Unless you are well-trained on proper use of ENCs (which often implies training on ECDIS), I strongly suggest not using the "standard" view and instead default to "all".

I believe this is an unfortunately collision between terminology (as per IHO's S-52 standard for chart content and display) and the general lack of training (and thus familiarization with the relevant standards) for recreational users. OpenCPN could perhaps address this in the UI with a "please don't use this" type of label.

Also, there's a feature request for OpenCPN here. I'm not sure if it already exists and I simply missed it, but I don't see an option to enable the "isolated dangers" display in waters shoaler than the safety contour.

"IHO S-52 Presentation Library Edition 4.0 requires that ECDIS have an additional function to highlight all isolated dangers that fall in the unsafe water behind the safety contour, as experience has shown that vessels often have to cross the safety contour when navigating in confined waters" -- https://www.admiralty.co.uk/news/imp...amiliarisation

[Chotu]

so, I agree that this is not good. However, what about that course? Why would you go on the wrong side of (or even approach) a hazard marker? If you look really closely at the track, it’s almost on top of the marker, but just barely on the wrong side of it. It's clearly orange and white in the ENC chart you are complaining about, even though it's under your track.

That is an orange and white striped can that always denotes a severe hazard. You went right over it, basically. Not good.

in real life, looking out at the horizon and at the markers, I’m not sure why that course would be chosen to begin with. it’s a very risky one.

I have to point out that this is a case of "get your head out of the electronics". The harbor is we laid out and the markers are appropriate no matter what the chart details are saying.

When navigating, it's more prudent to follow the course laid out by the markers (as you did leaving the harbor) than it is to try to cheat them to save 5 minutes.

PS: you dishonored nun 2A as well.

[rooiedirk]

See screenshots

[emilecantin]

Originally Posted by Chotu

so, I agree that this is not good. However, what about that course? Why would you go on the wrong side of (or even approach) a hazard marker? If you look really closely at the track, it’s almost on top of the marker, but just barely on the wrong side of it. It's clearly orange and white in the ENC chart you are complaining about, even though it's under your track.

That is an orange and white striped can that always denotes a severe hazard. You went right over it, basically. Not good.

in real life, looking out at the horizon and at the markers, I’m not sure why that course would be chosen to begin with. it’s a very risky one.

I have to point out that this is a case of "get your head out of the electronics". The harbor is we laid out and the markers are appropriate no matter what the chart details are saying.

When navigating, it's more prudent to follow the course laid out by the markers (as you did leaving the harbor) than it is to try to cheat them to save 5 minutes.

PS: you dishonored nun 2A as well.

I was busy handling sails, and the buoy is white in real life; looked very similar to "No Wake" or speed limit buoys which are everywhere around these parts. Never saw the orange. Depths were fine too.

I'll be the first to admit I wasn't really on top of my game here, but if I'd seen the rock on the chart, I would've paid more attention.

[emilecantin]

Originally Posted by requiem

I just loaded that ENC onto both OpenCPN and SEAiq, and hogback showed on both. I also had the "reduce detail at small scale" enabled, but that shouldn't affect this.

If you click the "reset to standard" button the rock symbol will disappear. Unless you are well-trained on proper use of ENCs (which often implies training on ECDIS), I strongly suggest not using the "standard" view and instead default to "all".

I believe this is an unfortunately collision between terminology (as per IHO's S-52 standard for chart content and display) and the general lack of training (and thus familiarization with the relevant standards) for recreational users. OpenCPN could perhaps address this in the UI with a "please don't use this" type of label.

Also, there's a feature request for OpenCPN here. I'm not sure if it already exists and I simply missed it, but I don't see an option to enable the "isolated dangers" display in waters shoaler than the safety contour.

I think that's it. I've always used the "standard" view, assuming that was the correct one to use. "All" is honestly a bit overwhelming (there's way too much text on there), but looks like "de-clutter text" is the way to tame this. Looking back with "All", it does show the rock there.

Thanks for the explanation.

[requiem]

Originally Posted by emilecantin

I think that's it. I've always used the "standard" view, assuming that was the correct one to use. "All" is honestly a bit overwhelming (there's way too much text on there), but looks like "de-clutter text" is the way to tame this.

So, a bit of back-story on why this is. There are two defined display categories, "base" and "standard". Base defines the minimum, i.e. no further elements can be removed, and is not intended for navigation. It may be useful for decluttering when planning. Standard sets a common but not too cluttered baseline, to which elements can be added or removed.

But, you say, the rock is a danger; shouldn't it show? Well, the rock is within the defined safety contour, and thus in theory you shouldn't be there to begin with; displaying the symbol would just add clutter. If the rock was in deeper water, it would be highlighted with an "isolated danger" symbol.

Properly setting the safety contour is not a complete solution, however: there isn't always going to be a depth contour at just the right level. Small craft (and even sailing vessels) will often find the next available contour covers water that's perfectly safe for them to navigate in. Even large ships will on occasion find they need to cross the safety contour.

This is why the presentation standard was updated to call for the ability to enable isolated dangers even in "unsafe" waters. For example, attached are screenshots of what my screen looks like using display category "standard", both with and without "isolated dangers in shallow areas" enabled.

[bdbcat]

requiem...


Nice explanation.
Thanks
Dave