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Old 16-09-2006, 12:56   #1
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DNC Vector compared to ENC vector chart?

Remember in the early days of GPS, when the military level of data availability was much better than the civilian data availability?

Is it just possible that the DNC vector chart to ENC vector chart difference is similar? Is the copyright argument just a smokescreen for such a defence based limitation?

Is there anyone on this list who can look at the some portion of the two underlying databases and shed any light on this?

ENC Vector charts are free for downloading at <http://nauticalcharts.noaa.gov/mcd/enc/index.htm>

RNC raster charts are free for downloading at <http://nauticalcharts.noaa.gov/mcd/Raster/Index.htm>

For those of you unfamiliar with DNC vector charts Look at the DNC chart site at

<http://www.nga.mil/portal/site/dnc/>

Digital Nautical Chart (DNC®)

The Digital Nautical Chart® is produced by the National Geospatial-Intelligence Agency (NGA) and is an unclassified, vector-based, digital database containing maritime significant features essential for safe marine navigation.

Initial data collection of the database is from a portfolio of approximately 5,000 nautical charts that will ultimately provide global marine navigation between 84° North latitude and 81° South latitude and support a variety of Geographic Information System applications.

There is a DNC FAQ page which might help clarify some issues, particularly about cost and availability:

<http://www.nga.mil/portal/site/dnc/index.jsp?epi-content=GENERIC&beanID=171498598&viewID=detail_vie w>

Of interest to cruisers, and my reason for asking the question is this from the DNC folks:

DNC is in a format called VPF (Vector Product Format), which uses a table based georelational data model and supports GIS applications such as mission planning, command and control, and situational awareness. This data is primarily used by the US Navy, Coast Guard, and other DoD agencies. VPF format is just a different format than S-57/S-63 format and which does meet IHO requirements for navigation. As per the caveats on our homepage, DNC is approved for navigation for federal vessels only. Regulations for civil use of electronic chart navigation have not yet been issued for U.S. waters and CIVIL VESSELS ARE NOT TO USE DNC® FOR NAVIGATION. DNC® is being made available to the public for GIS use only. While we do have DNC for world-wide navigation for our military customers, only DNC in US waters can be made available to the general public due to copyright restrictions with foriegn countries.
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Old 16-09-2006, 13:33   #2
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I don't think it's any such deceptive reason, although heaven knows we have plenty of reason to question government statements these days.

Rather, I believe the statement quite accurately reflects the difference between US Government-produced products -- which are not and have never been copyrighted -- and those of many/most other countries which do not allow the free copying or publication of their charts and other products.

The thought in this country has always been that a U.S. Government-produced product was paid for by the American people and should, therefore, be freely available for the public to use as they wish. If you buy a USG publication and copy it at the nearest Kinko's, you're free to sell the copy or trade it or do whatever you want with it. Other countries, in general, don't allow that.

So, I suspect that we have agreements with the producers of charts in other countries to use their chart data for USG users only, and not make what is essentially their data available freely to anybody. Just a guess.

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Old 16-09-2006, 13:56   #3
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Quote:
Originally Posted by btrayfors
I don't think it's any such deceptive reason, although heaven knows we have plenty of reason to question government statements these days.
SNIP
Bill
Given:
ENC Vector charts are free for downloading at <http://nauticalcharts.noaa.gov/mcd/enc/index.htm>

RNC raster charts are free for downloading at <http://nauticalcharts.noaa.gov/mcd/Raster/Index.htm>

and that there is inexpensive software for PCs and Macs

PC based: <http://www.fugawi.com/web/products/fugawi_marine_enc.htm>

Mac based:

<http://www.gpsnavx.com/MacENC/>
<http://www.gpsnavx.com/>
Leaving aside, for the moment, issues of copyright, availability, and software to read the DNC charts, would the DNC charts be superior to the now widely used ENC charts? Is the ENC to DNC quality analagous to the old days of GPS precision?
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Old 16-09-2006, 14:16   #4
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I don't know the answer to that. Maybe someone else here does.

Two notes, however.

1. ENC and RNC charts are available for the U.S. waters ONLY (whereas the charts DNC is referring to are for foreign waters); and

2. I doubt whether the ENC and RNC charts have been "degraded" in the same way the GPS signal was corrupted when Selective Availability (SA) was turned on. More likely, the DNC versions may have some new data which has not been incorporated into the other charts.

Bill
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Old 16-09-2006, 19:39   #5
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I haven't had a chance to look into the format differencesw, but would bet the copyright reference "only DNC in US waters can be made available to the general public due to copyright restrictions with foriegn countries." is simply because the DoD has obtained permission for military/intelligence use of British Crown or Admiralty copyrighted material, and similar material, and has no right to redistribute it.

Similarly, one might note that non-US-citizens have no right to US government publications. USG publications are not copyright free, but rather, the copyright belongs to "we the people" and that means the citizens only. I've never seen that clarified, formalized, or enforced against anyone else--but there very much IS a copyright in effect.

Some years and a number of agency nomenclatures ago, I had a discussion with...let's call him a mapmaker, at one of the federal agencies. He said no, he didn't have certain data, and I said yes, I know you do have it because (specifics) and you'd be derelict in your duties if you hadn't gotten it. So, if I asked nicely, could I just see what you have on that one spot on your chart? Not everything you have, but just one spot on one chart? It was possible, with a 90-day delay while they're checking out exactly who the hell you are. These days...or in other locations...

Everyone is paranoid. NGIA, who can't figure out how to spell their own acronym, even think some of their material is copyrighted to them privately "because we put our logo in it and no one else can use our logo."

I wouldn't be surprised if the DNC format differed from ENC only by being a "superset" that allowed strategic information to be overlaid and used with the charts--by authorized users. Or, distorted and diddled by "civilian" vs. government users, like the GPS streams.

Heck, even the NSA and CIA banned FURBIES from their buildings, because n one could be sure what the computer code in them really could do!
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Old 16-09-2006, 20:00   #6
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Following is from the U.S. Copyright Office (Library of Congress) website:

"Publications Incorporating U. S. Government Works

Works by the U. S. government are not eligible for U. S. copyright protection. For works published on and after March 1, 1989, the previous notice requirement for works consisting primarily of one or more U. S. government works has been eliminated. However, use of a notice on such a work will defeat a claim of innocent infringement as previously described provided the notice also includes a statement that identifies either those portions of the work in which copyright is claimed or those portions that constitute U. S. government material.
Example: &#169; 2006 Jane Brown. Copyright claimed in Chapters 7—10, exclusive of U.S. government maps
Copies of works published before March 1, 1989, that consist primarily of one or more works of the U. S. government should have a notice and the identifying statement."



Following is from the CENDI Copyright Working Group Secretariat...
"3.1.2 Is a U.S. Government work provided copyright protection?
In the United States, U.S. Government works are covered by 17 USC &#167; 105.59 "Copyright protection … is not available for any work of the United States Government, but the United States is not precluded from receiving and holding copyrights transferred to it by assignment, bequest, or otherwise." Exceptions are available for certain works of the National Institute for Standards and Technology (NIST) and the U.S. Postal Service. Copyright protection may be available for U.S. Government works outside the United States (see FAQ Section 3.1.6). When a copyrighted work is transferred to the U.S. Government, the Government becomes the copyright owner and the work retains its copyright protection."
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Old 16-09-2006, 22:05   #7
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NGIA, who can't figure out how to spell their own acronym, ...
I don't know why anybody would have trouble spelling the acronym for Defense Mapping Agency (DMA), uh... I mean "National Imagery and Mapping Agency" (NIMA), uh.. I mean "National Geospatial Intelligence Agency" (NGIA)...

Quote:
Heck, even the NSA and CIA banned FURBIES from their buildings, because n one could be sure what the computer code in them really could do!
Recall that Furbies were marketed as toys that learned from their owners by interaction, and there was some indication that they could record and replay sounds from their environment. It was the "record and replay" that disturbed the spy agencies.

Of course, there are procedures for taking certain materials in/out, so if somebody had a work-related reason to have a Furby in the building (say it spent some time in a KGB office), then it could be arranged.


Quote:
As per the caveats on our homepage, DNC is approved for navigation for federal vessels only. Regulations for civil use of electronic chart navigation have not yet been issued for U.S. waters and CIVIL VESSELS ARE NOT TO USE DNC® FOR NAVIGATION.
I have another obvious interpretation that nobody mentioned yet: We aren't authorized to accept liability for you using our charts in civilian applications. If you do, and you wreck your boat, it's not our fault. So there.
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Old 17-09-2006, 12:11   #8
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Quote:
Originally Posted by adjuvantjfoster
Given:
SNIP
Leaving aside, for the moment, issues of copyright, availability, and software to read the DNC charts, would the DNC charts be superior to the now widely used ENC charts? Is the ENC to DNC quality analagous to the old days of GPS precision?
ENC charts are available worldwide from a number of sources. Not just Noaa or the US government agencies. For example

HTML Code:
http://www.transas.com/products/onboard/ecs/tx97/
Quote:
Since the year 2000, Transas has been an official and exclusive distributor of the Russian Federation Chief Administration of Hydrography and Oceanography for S-57 charts. Since 2004 Transas is an official distributor of charts in SENC (System Electronic Navigation Charts) format from the world main ENC providers: IC-ENC and PRIMAR Stavanger.
HTML Code:
http://www.ic-enc.org/page_coverage_catalogue.asp
Quote:
members of the two leading ENC centres – PRIMAR-Stavanger and IC-ENC – have joined forces to create a comprehensive guide to charts and chart carriage requirements.
HTML Code:
http://www.primar-stavanger.org/
Quote:
The service has been in full operation since April 2002, and include today official ENCs from more than 30 countries.
No doubt that ENC is the presently accepted vector chart standard.

As an example, Nobeltec, a popular UK-based PC charting application, licenses its vector charts from Transas. While in turn Transas is an official distributor of charts in SENC (System Electronic Navigation Charts) format from the world main ENC providers: IC-ENC and PRIMAR Stavanger.

In the future, would digital navigation be better off with DNC vector charts?
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Old 17-09-2006, 18:19   #9
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ENC is an international standard and the "only electronic format" legal for those ships required by international law to maintain charts. So for them it is ENC or paper. This of course is commercial vessels and not really about cruisers. The issue is they are the only offical electronic formats. Nothing else is when in electronic format. ENC can be "patched". The RNC US charts are created from the exact data base use to make the ENC charts and for cruisers there should be no significant issues. I like the seamless nature of ENC. You load as many as you want and you have one unified chart.

It is not to say other formats are not more "usefull". I find the Navonics chips to be a quite rich set of data and in a format that is easy to use. I just recently got a handheld unit that uses these chips and the charts are very nice to look at and use. Utility does matter as well.

There are other propritary standards (oxymoron) to be used with proprietary devices. So you buy brand X chart plotter you can only use brand X data - get the idea? When it's the only data that works with the device what do standards mean?

As far as standards go ENC is the only maritime navigation standard. In the consumer market it's what ever they can sell you. In a global sense there is no universal data set that is standard that you can get with a one stop shopping trip.
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