Playtime
Well-Known Member
Don't you just love "holier than thou".
I thought this argument had been done to death elsewhere so I suggest we drop it from this thread now.
Charts for CPN
- Thread starter Coaster
- Start date
Don't you just love "holier than thou".
I thought this argument had been done to death elsewhere so I suggest we drop it from this thread now.
lustyd
Well-Known Member
Thank you oh wise one. I think I understand now. What you're saying is that when I need a new television I should take one from someone on the dole because technically it was I who payed for it?
bromleybysea
Well-Known Member
Thank you oh wise one. I think I understand now. What you're saying is that when I need a new television I should take one from someone on the dole because technically it was I who payed for it?
Probably as good an example of sophistry as I've come across. But this is now one for the Lounge, that realm of bigoted crackpots, and I'm not venturing there!
elton
Well-Known Member
I agree, the discussion is tedious. But I felt the need to correct your fatuous misinformation.Don't you just love "holier than thou".
I thought this argument had been done to death elsewhere so I suggest we drop it from this thread now.
Playtime
Well-Known Member
I'll ignore the "fatuous" but maybe you could explain what you mean by "misinformation". What I said was perfectly reasonable and correct.
lustyd
Well-Known Member
I suspect it was the implication that it was OK to use them that he was referring to, and when you said dubious legality rather than illegal. Everything else you've said has been pretty helpful.
elton
Well-Known Member
Exactly.
affinite
Well-Known Member
To the OP
Ignoring the squabling re illegal chart downloads ...
I had Maptech Offshore Navigator but gave up on it because I wanted AIS overlay.
I changed to OpenCPN last year and Im delighted with it. It was able to read my existing BSB charts and Ive incoporated AIS from an Advansea receiver.
System works just great except I cant get the Autopilot/Route/Waypoint data out to my cockpit repeater. All in all a great piece of (Free) software.
Sorry I cant help with the technicalities re BSB but it does work somehow.
Ignoring the squabling re illegal chart downloads ...
I had Maptech Offshore Navigator but gave up on it because I wanted AIS overlay.
I changed to OpenCPN last year and Im delighted with it. It was able to read my existing BSB charts and Ive incoporated AIS from an Advansea receiver.
System works just great except I cant get the Autopilot/Route/Waypoint data out to my cockpit repeater. All in all a great piece of (Free) software.
Sorry I cant help with the technicalities re BSB but it does work somehow.
Blue5
Well-Known Member
I'd think a good percentage of peeps using Open CPN are doing it with "illegal" charts downloaded from the internet.
Cruisers Forum have a dedicated board for Open CPN so if you have queries it is a good source of information
Cruisers Forum have a dedicated board for Open CPN so if you have queries it is a good source of information
lustyd
Well-Known Member
Overner
Well-Known Member
Raster Charts for OpenCPN dated 2nd July 2012
Hi All,
Apart from the legality of using downloaded CM93 charts which are most certainly NOT in the public domain, there is another point.
Raster vs. Vector. The CM93 charts I guess are OK for open waters. But anyone who's looked at them will tell you that they lack a great deal of detail when it comes to close quarters stuff.. like getting into a strange harbour/river/estuary, etc.
OpenCPN makes a good job of dealing with Raster charts, and these will give you absolutely all the detail you'd get in a standard Admiralty paper chart. But you will be positioned on it, show AIS targets on it, etc.
The best solution is to use whatever charts you can get freely for areas you can't get decent legal charts for... but to buy up to date legal charts for the areas you can get them. It's your safety that's at stake, and on a dark windy night up an unfamiliar estuary wouldn't you rather have a familiar looking chart with ALL the details visible ?
We at VisitMyHarbour are great fans of free or cheap navigation programs, and specifically make compatible charts for them. We don't think you should be paying £100's for card readers, programs etc. Judging by the way our SeaClear package sells, we tend to think boat owners agree too...
Check out this article by Richard Fairman where he tests out 4 great free/cheap nav programs over 1000 sea miles:
http://www.visitmyharbour.com/chartplotter-sea-tests.asp
And specifically we now make a "ChartStick" with July 2012 UK/Irl charts that is 100% compatible with OpenCPN, Polar Navy... and also Google Earth as an option.
http://www.visitmyharbour.com/charts-for-opencpn.asp
Initial cost is a little pricey at £54 odd, BUT £25 of that is the deposit on the hardware dongle. Future editions (we tend to make 2 a year), can be built onto the same dongle for £20-£25. The dongle is portable between any number of Windows machines, use at home or on the boat.
Kind Regards to all,
Steve
Hi All,
Apart from the legality of using downloaded CM93 charts which are most certainly NOT in the public domain, there is another point.
Raster vs. Vector. The CM93 charts I guess are OK for open waters. But anyone who's looked at them will tell you that they lack a great deal of detail when it comes to close quarters stuff.. like getting into a strange harbour/river/estuary, etc.
OpenCPN makes a good job of dealing with Raster charts, and these will give you absolutely all the detail you'd get in a standard Admiralty paper chart. But you will be positioned on it, show AIS targets on it, etc.
The best solution is to use whatever charts you can get freely for areas you can't get decent legal charts for... but to buy up to date legal charts for the areas you can get them. It's your safety that's at stake, and on a dark windy night up an unfamiliar estuary wouldn't you rather have a familiar looking chart with ALL the details visible ?
We at VisitMyHarbour are great fans of free or cheap navigation programs, and specifically make compatible charts for them. We don't think you should be paying £100's for card readers, programs etc. Judging by the way our SeaClear package sells, we tend to think boat owners agree too...
Check out this article by Richard Fairman where he tests out 4 great free/cheap nav programs over 1000 sea miles:
http://www.visitmyharbour.com/chartplotter-sea-tests.asp
And specifically we now make a "ChartStick" with July 2012 UK/Irl charts that is 100% compatible with OpenCPN, Polar Navy... and also Google Earth as an option.
http://www.visitmyharbour.com/charts-for-opencpn.asp
Initial cost is a little pricey at £54 odd, BUT £25 of that is the deposit on the hardware dongle. Future editions (we tend to make 2 a year), can be built onto the same dongle for £20-£25. The dongle is portable between any number of Windows machines, use at home or on the boat.
Kind Regards to all,
Steve
Conachair
Guest
Errm, are you sure? Mine look pretty much identical to the ones on your website. Some text , like anchorage notes, you need to double click to get to but otherwise the same. I much prefer vector these days as it gets rid of all the fine detail you don't need as you zoom out, though that's all adjustable anyway.
AntarcticPilot
Well-Known Member
For a map that may be zoomed, vector is infinitely preferable to raster. Raster can easily fail to display objects as it is zoomed out. This is because the display software has to resample the raster data at reduced resolutions; this resampling can remove small objects, reduce line quality for linear features, and change any small ornamentation on filled areas. With vector data, the choices made in zooming out are under control and can be predicted; with raster data they aren't and can't. Vector is also a) more efficient in terms of storage space, b) allows invisible information to be tagged to objects and c) can be displayed using a variety of styles as preferred - for example, Day/Night colours (though this capability should be used with care). Finally, as Conochair has said, you can remove detail if this gets in the way.
haydude
Well-Known Member
Search the torrent for CM93 charts and you will find the whole world up to date to 2010.
Every UK charts is NOT covered by copyright which expired several years ago. Simple updates are too not covered by Copyright standing to the law, vendors do protect their updates using new encrypted formats, but if these can be read otherwise they cannot enforce any right.
Our coastlines belong to us all and the information about them is of public domain.
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Elemental
Well-Known Member
Overner is correct. CM93 charts do not show drying heights at all. Absolutely essential if picking your way up an estuary where the channel might meander all over the place...
Elemental
Well-Known Member
But the big omission is the total lack of provision for linux users. So, at the very least, you have to add the cost of around £100 or so for a Windows license to run in a VM...
Conachair
Guest
Yep, right are about drying heights, just checked. But very different from "lacking a great deal of detail".
Overner
Well-Known Member
Raster vs Vector and CPN
Probably best to agree the Raster Vector thing is down to personal choice. Raster charts are not susposed to be viewed at more than 100% size in any navigation program, or as pointed out, they are working beyond the limits they were designed for. But when you have a complete set of rasters at all scales there's no need to ever be on an overzoomed chart.
For those who really want to find out about the Raster/Vector issues, download this PDF from CherSoft (the people who do Easy Tide)
www.chersoft.co.uk/Resources%5CCherSoft_RasterVector.pdf
OK let's have a look.. here's a small sample of a raster chart of Cowes, at about 70% of full size:
It may be interesting to see this exact same area lifted from a CM93 vector chart ? Would anyone care to post an image ?
Anyway, we fully support OpenCPN and their aims.. co-operation is the way to go. We do believe that users of this program should at least have the choice of being able to use bang up to date legal charts at a good price and will do our best to provide.
All the best,
Steve at VMH
Probably best to agree the Raster Vector thing is down to personal choice. Raster charts are not susposed to be viewed at more than 100% size in any navigation program, or as pointed out, they are working beyond the limits they were designed for. But when you have a complete set of rasters at all scales there's no need to ever be on an overzoomed chart.
For those who really want to find out about the Raster/Vector issues, download this PDF from CherSoft (the people who do Easy Tide)
www.chersoft.co.uk/Resources%5CCherSoft_RasterVector.pdf
OK let's have a look.. here's a small sample of a raster chart of Cowes, at about 70% of full size:
It may be interesting to see this exact same area lifted from a CM93 vector chart ? Would anyone care to post an image ?
Anyway, we fully support OpenCPN and their aims.. co-operation is the way to go. We do believe that users of this program should at least have the choice of being able to use bang up to date legal charts at a good price and will do our best to provide.
All the best,
Steve at VMH
AntarcticPilot
Well-Known Member
The point with raster charts isn't overzooming; that is a BAD THING on any digital chart, and ideally your hardware/software will not allow you to do this (Memory Map doesn't, and neither does my Raymarine C80; I have little experience of other systems). However, raster charts certainly WILL lose objects as you zoom out, because the raster has to be resampled to fit the display reolution. So, small objects - symbols, lines and so on - will certainly be distorted by the resampling, and in the worst case, actually removed from the display. Narrow lines are the worst case.
This is a standard problem in all geographic information systems, and the answer is that non-image raster data should only be used at the intended scale, neither zoomed in nor zoomed out. Vector data are more reliable, and more flexible in terms of zooming etc. Vector data have other advantages (ability to add non-visible attribute data, ability to allow selection of visible features, relatively small demands on data transfer and storage). In GIS (of which chart plotters are an example), the battle between vector and raster representation of data was won by vector (for most purposes) long ago. Raster maps are normally only used for context, not as informational layers of a Geographic Information System.
I should note that the international standard for electronic charting, S57, is a vector format. This is the standard set by the IHO.
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sailorman
Well-Known Member
Probably best to agree the Raster Vector thing is down to personal choice. Raster charts are not susposed to be viewed at more than 100% size in any navigation program, or as pointed out, they are working beyond the limits they were designed for. But when you have a complete set of rasters at all scales there's no need to ever be on an overzoomed chart.
For those who really want to find out about the Raster/Vector issues, download this PDF from CherSoft (the people who do Easy Tide)
www.chersoft.co.uk/Resources%5CCherSoft_RasterVector.pdf
OK let's have a look.. here's a small sample of a raster chart of Cowes, at about 70% of full size:
It may be interesting to see this exact same area lifted from a CM93 vector chart ? Would anyone care to post an image ?
Anyway, we fully support OpenCPN and their aims.. co-operation is the way to go. We do believe that users of this program should at least have the choice of being able to use bang up to date legal charts at a good price and will do our best to provide.
All the best,
Steve at VMH
It is an old copy
