Old dog new tricks

[Refueler]

This is a benefit of raster charts - it is a feature and not a bug. When you can see the pixels you know that you're viewing the wrong scale of chart, and you should switch to a larger scale chart.

OpenCPN can automatically change to a more suitable sale of raster chart for you, it works somewhat well, or you can change manually.

What you say is actually a disadvantage of vector charts - if you zoom in too far using a vector chart then there is nothing to indicate the absent details, you just get a smooth curve and no indicators of rocks, shallows, buoys etc.

Anyone can see this for themselves using NOAA's enc charts of North America - both US2EC02M and US5NC1LP cover the New River at Jacksonville. NC, but the first covers Cape Hatteras to Straits of Florida at 1:1,200,000 scale and the other is at 1:12,000 scale. You can load these up on your PC and the whole of the US east coast is covered at 3 different scales.

There seems to be an attitude on this forum that vector charts are "obviously" better than raster charts, like vector sag files are "obviously" better than jpegs or goes. You only have to look for yourself and see that this is not always the case.

Time to update your views ...

Even UKHO is moving away from Raster.

Raster was based on the digitising of the paper chart archives and UKHO moving towards ECDIS .... UKHO as example moved to digital correction of their charts .. even to no longer carrying physical templates ...

A good chart system - based on an area folio - will auto select seamlessly the next scale detail as you progressively zoom in ... note I am not talking raster .. I am talking vector. The days of just zooming in on one vector chart is old hat ... The base chart stays - but the detail levels change as you zoom in / out. Your argument of vector detail staying without changing is really old hat ...

I have more chart systems than most on these forums ... as I have access to commercial as well as retail.
As to OpenCPN ... mmmm lets be honest - OpenCPN became popular because of the coding for CM93v2 becoming common knowledge and being integrated into OpenCPN. Now people could have worldwide coverage free of charge. To quote OpenCPN for Raster - I accept - but also must comment that I reckon most users are still using CM93v2 ... which stopped being updated about 2015~ .... and even that is questionable .. as CM93v3 was already delivered ...
But of course v3 - OpenCPN cannot use.

There are better chart programs out there than OpenCPN ! Some even can use CM93v3 ..... I will not answer here or via PM the program links / names due to Licence restrictions.

 

[onesea]

A good chart system - based on an area folio - will auto select seamlessly the next scale detail as you progressively zoom in ... note I am not talking raster .. I am talking vector.

For me the problem with this is the detail that is lost as you zoom out.
Paper charts often show "relatively" small hazards to navigation even on larger scale charts.

Not something that I have found from the algorithms that decide the detail to be displayed on Vector Charts.

When I say relatively small I mean the rock, bank or obstruction. That is a hazard to navigation however it's only small in size and could be considered not relevant at a larger scale.

Paper charts have been developed over centuries to keep relevant hazards on charts.

IMHO the algorithms just have not caught up, yet. I am sure they will.

I still use navionics just with caution.

 

[Refueler]

When I say relatively small I mean the rock, bank or obstruction. That is a hazard to navigation however it's only small in size and could be considered not relevant at a larger scale.

mmmm not sure I can accept that ... if its a hazard to shipping - it will be shown. Not relevant ??

 

[doug748]

I know the difference between Gnomonic projection and Mercator projection charts. I am reasonably confident if push came to shove I could just about get away using a sextant. I will admit I had to look up the difference between Raster and Vector charts. I like being a dinosaur at least being one it does not tie my head in knots trying to deal with all the new to me techometry. Thank you every one between you all you have helped me a lot I will include YouTube as well as it is a good teaching tool. If I buy this boat I will be using A bit of everything mentioned in the replies. I wish you all a good boating summer.

Looks like the plotter is in the cockpit, you will love it esp if singlehanded. I have two, one I use with 12 year old charts and one I keep as backup with 20 year old charts. Fear not as I also have paper charts but they are probably 30 years old In fact there are few circumstances where out of date plotter charts matter - and they are mainly predictable.

What is very very useful is AIS, which is unlikely to be handled by your prospective new set. Hope it goes well.

.

 

[stu9000]

I bought one of these android car stereos , put it in an enclosure and mounted it under the hood. Runs navionics. Good in strong sunlight. Still going strong after 3 seasons +.

9" Android 13 Double 2 DIN Car Stereo Radio GPS Navigation WIFI Bluetooth FM RDS | eBay
Sure , if you are going round the Horn, you might want something more marinised but I've got various phones and tablets as back up and this has never fritzed out on me no matter how wet or damp the conditions. If you can wire a plug, you can do this.

 

[Geoff A]

Looks like the plotter is in the cockpit, you will love it esp if singlehanded. I have two, one I use with 12 year old charts and one I keep as backup with 20 year old charts. Fear not as I also have paper charts but they are probably 30 years old In fact there are few circumstances where out of date plotter charts matter - and they are mainly predictable.

What is very very useful is AIS, which is unlikely to be handled by your prospective new set. Hope it goes well.

Thank you and a thank you every one else who replied. If it all goes OK for 99% of the time I will be sailing single handed

.

 

[onesea]

mmmm not sure I can accept that ... if its a hazard to shipping - it will be shown. Not relevant ??

Below screen shots show my distrust.

Entrance to Beaulie.
Rasta on memory map:






I can know what the chart is showing me. And that there are further charts available.

On Navionics:
You have to zoom close in to see the finer detail at which point the screen becomes useless for non GNSS navigation.






Vector Software is generally improving but I don't want to be zooming in and out all the time for the best information.
Also having to check settings to get the information I want.

 

[GHA]

On Navionics:
You have to zoom close in to see the finer detail at which point the screen becomes useless for non GNSS navigation.

To be fair though that's not the fault of vector charts, that's the fault of Navionics which is dumbed down one size fits all that anyone can use. High end progs like opencpn will allow a great deal of control over what does or doesn't get displayed & the level of detail at different zooms. But it's like comparing a basic picture viewer on your phone to full blown photoshop, most won't bother learning when navionics works fine.

 

[dunedin]

For me the problem with this is the detail that is lost as you zoom out.
Paper charts often show "relatively" small hazards to navigation even on larger scale charts.

Not something that I have found from the algorithms that decide the detail to be displayed on Vector Charts.

When I say relatively small I mean the rock, bank or obstruction. That is a hazard to navigation however it's only small in size and could be considered not relevant at a larger scale.

Paper charts have been developed over centuries to keep relevant hazards on charts.

IMHO the algorithms just have not caught up, yet. I am sure they will.

I still use navionics just with caution.

I agree with this specific issue. Isolated small rocks which come up steeply from deep water, which are not unusual in Scottish, Norwegian and some Swedish waters, can be very difficult to spot in Navionics (and some other chart presentations), particularly in sunlight - as there is sometimes just a faint cross on the consistent blue colour depth (because there is no wider area of shallow water around it).
This is not a generic issue of vector vs raster, but is a result of poor design / programming in some vector chart sofware (including Navionics). Hence I often use BOTH Navionics / vector (on the plotter) and UKHO raster (on the tablet) in rocky waters.

 

[Refueler]

To be fair though that's not the fault of vector charts, that's the fault of Navionics which is dumbed down one size fits all that anyone can use. High end progs like opencpn will allow a great deal of control over what does or doesn't get displayed & the level of detail at different zooms. But it's like comparing a basic picture viewer on your phone to full blown photoshop, most won't bother learning when navionics works fine.

Correct - its the fault of the program / app displaying the chart ...

ALL the information is there in all zoom levels - but because Vector is layered - the program displays the layers decided by author of the program - or as GHA rightly says - other programs give the user options on layers displayed.

Lets consider zooming out on raster vs vector ... raster will not maintain text or images in layered form - its just basically a bmp and all detail will scale down with the rest of the chart ... so it does not get cluttered with symbols etc.
Vector on the other hand being layered and designed to remain readable - will tend to clutter a heavily zoomed out display - and is one of the reasons 'user defined layers' is used.
Next raster is a one scale chart .. the scale picked in the paper days to most useful scale deemed at that time. Vector has introduced the zoom factors that give user ability to study intently an area or zoom out ..

Conclusion : The program used to display the charts will make a huge difference on how the information is presented or not. I agree that the app for Navionics does interfere with users ability to choose layers ... but its NOT Navionics fault. Its the app.

 

[Seasick Steve]

A decent raster chart system (I use Marine Navigator) will automatically select the appropriate scale - the largest scale chart available, just like we're supposed to do with real charts. Or you can override this and select the scale manually. Then you get the level of detail appropriate to where you are.

As far as AIS is concerned I can't see the benefit for small boats. In the Solent and other crowded waters it goes off all the time. In the open sea in decent visibility (provided you're observing Rule 5) you can see other vessels in plenty of time to take avoiding action. When it's foggy, anchor in shallow water.
I can see it's useful on a ship's bridge where (illegally) there may not be a lookout.

 

[Refueler]

A decent raster chart system (I use Marine Navigator) will automatically select the appropriate scale - the largest scale chart available, just like we're supposed to do with real charts. Or you can override this and select the scale manually. Then you get the level of detail appropriate to where you are.

[/QUOTE]
Which in effect and result is not different to Vector Charting - except that Vector Charting had ability to have layers turned off / on by user .. Raster is set as its a BMP file ... so details are dependent on the chart you choose ... ie offshore - approaches - harbour etc.

As far as AIS is concerned I can't see the benefit for small boats. In the Solent and other crowded waters it goes off all the time. In the open sea in decent visibility (provided you're observing Rule 5) you can see other vessels in plenty of time to take avoiding action. When it's foggy, anchor in shallow water.
I can see it's useful on a ship's bridge where (illegally) there may not be a lookout.

AIS ... of course in well frequented waters - it can be a real pain ...

But you spoil that section of post with the "I can see it's useful on a ship's bridge where (illegally) there may not be a lookout." A statement which shows confusion.

Lookout is not OOW ... but OOW can be Lookout. Lookout is term for the seaman detailed to be 'lookout' to assist the OOW .... depending on the location and where unlikely shipping - it is common for that seaman to be carrying out another duty but always in contact with OOW for recall to bridge.

 

[NormanS]

For me the problem with this is the detail that is lost as you zoom out.
Paper charts often show "relatively" small hazards to navigation even on larger scale charts.

Not something that I have found from the algorithms that decide the detail to be displayed on Vector Charts.

When I say relatively small I mean the rock, bank or obstruction. That is a hazard to navigation however it's only small in size and could be considered not relevant at a larger scale.

Paper charts have been developed over centuries to keep relevant hazards on charts.

IMHO the algorithms just have not caught up, yet. I am sure they will.

I still use navionics just with caution.

I think that you, and you're not alone, are confused by the terms "large" and "small" scale. For the avoidance of doubt, a large scale chart covers a smaller area at a large scale, and would be expected to show more detail.

 

[Refueler]

I think that you, and you're not alone, are confused by the terms "large" and "small" scale. For the avoidance of doubt, a large scale chart covers a smaller area at a large scale, and would be expected to show more detail.

I really don't see the argument about detail on Vector ... as a trained professional navigator - I always check various scales of chart for an area when approaching land / harbour etc. I never rely on one scale

When I was on ships ... it was common on approaches to have two paper charts on the table .. small and large scale - reference made to both as approach made .. one to give an overall aspect of approach - the other to give detail at position ...