Visit our Popular Forums

sv_isara · 09-11-2021, 10:02

Hey all, I see there are a lot of articles and threads on how to use open CPN, which I do and am still learning. However (at the risk of people sarcastically offering to google something for me, which I've done) my question comes from the useage of an old Garmin GPSMap 182C plotter, compared to the columbia river charts downloaded for free from the government.

The free Open CPN charts was ok, but ultimately didn't have any real detail for where I was (Multnomah channel to be specific, chart 18525), whereas the Garmin bluechart had an astonishingly more detailed map. The garmin looked like a vector vs a paper chart projection, but also had more granular detail by far. Don't have pics, but the example would be - OpenCPN would have one depth sounding across the channel where Garmin would have 2 or 3 with additional detail.

My question is - is there a summary of the major different digital chart sources, and how many of them are proprietary, and how many of them are not going to be useable on OpenCPN due to that? For the PNW, Mexico, and the South Pacific (and beyond), what are my best digital chart sources?
Thanks for any help!

edit has anyone seen/used this?http://svocelot.com/Cruise_Info/Equipment/mbTiles.htm

rgleason · 09-11-2021, 16:39

Sharky, there is a considerable amount of detail about obtaining charts for the US and all over the world in the "USER MANUAL". You might try using it and you don't even need to use google search (yes google is watching your every move, so don't get spooky). What we have is an inline search right at the top that you should use.

You just have to put "Charts" at the top. You might even get more sophisticated than that, but charts should work. Good Luck.

Oh by the way, the User Manual is most easily found from the website opencpn.org.
I suggest you bookmark it.

sv_pelagia · 09-11-2021, 17:28

Quote:

Originally Posted by sv_sharky

Hey all, I see there are a lot of articles and threads on how to use open CPN, which I do and am still learning. However (at the risk of people sarcastically offering to google something for me, which I've done) my question comes from the useage of an old Garmin GPSMap 182C plotter, compared to the columbia river charts downloaded for free from the government.

The free Open CPN charts was ok, but ultimately didn't have any real detail for where I was (Multnomah channel to be specific, chart 18525), whereas the Garmin bluechart had an astonishingly more detailed map. The garmin looked like a vector vs a paper chart projection, but also had more granular detail by far. Don't have pics, but the example would be - OpenCPN would have one depth sounding across the channel where Garmin would have 2 or 3 with additional detail.

My question is - is there a summary of the major different digital chart sources, and how many of them are proprietary, and how many of them are not going to be useable on OpenCPN due to that? For the PNW, Mexico, and the South Pacific (and beyond), what are my best digital chart sources?
Thanks for any help!

edit has anyone seen/used this?http://svocelot.com/Cruise_Info/Equipment/mbTiles.htm

A lot of questions... difficult to answer for every area!

"Free charts" on OpenCPN? Excluding NOAA charts for the USA (which are free and the best), what other free charts are you referring to? CM93 are free but are also pirated and many years out of date.

A few countries do provide their charts for free - - the USA is a good example. Canada and Mexico do not....

Certainly, for USA, NOAA raster and vector charts far superior.

Not sure how you mean NOAA chart 18525 Multnomah lacks detail. It is vefy detailed! See this pdf. http://www.charts.noaa.gov/PDFs/18525.pdf

MBTILES? I use them all the time for uncharted/poorly charted areas. I use SAT2CHART and SASPLANET to make them up. BUT these are NOT nautical charts! (Although can make mbtiles of Navionics and CMAP charts through SASPLANET and SAT2CHART, an arduous process.)

In Canada, where I am and now my only cruising area, official CHS charts are the ONLY charts (for Canada) that you can update and be certain they are up-to-date.* I find Navionics takes too long to apply updates (e. g., rocks and shallows), and sometimes doesn't get around to them at all. CMAP is even worse.

*HOWEVER, I have been using/investigating O-Charts (vector charts specifically for OpenCPN) and am finding them reasonably priced and, importantly, up-to-date (for Canada).

https://www.o-charts.org/

O-Charts will be coming out with vector charts for Mexico based on official SEMAR charts, and these will be updatable on a weekly basis. O-Charts also provides the excellent Blue Latitude harbour/anchorage chartlets.

HeywoodJ · 09-11-2021, 18:09

The OpenCPN manual has a pretty good list of the free sources of official charts here.

I suspect the difference in what you saw, if using the NOAA chart in O, is that with vector charts there are a ton of settings for how much data to display. There is a bit of a learning curve with O in how to configure things in a way that pleases each user and each use case.

Alternatively, some of the chartplotter companies add additional data from sources other than official hydrographic surveys. Most of them do not provide a lot of clarity on what data, how they collect it, and what accuracy it has. Regardless, that can lead to the display of data that is not on the official chart.

If you were to post a screenshot of your O display someone here could comment on what settings to tweak to get the display you expect.

bbalan · 15-01-2024, 16:12

The most important thing is to have MULTIPLE sources of charts in OpenCPN. ALL charts have errors -- whether downloaded from NOAA, Navionics, or MBTiles made form satellite images. So you want to be able to switch between these sources easily to compare. That's one of the incredibly awesome features of OpenCPN (use Chart Groups!).

Free MBTiles charts for nearly all of the Pacific, Mexico, NZ, etc. are available at TheChartLocker.com.

Cheers,
Bruce