I was shocked to read that NOAA is canceling production of paper charts. I'm confused. Can anyone explain what the implication of this is, exactly? Surely the traditional Maptech chart kits will still be available, right? I thought they were based on "art" produced by NOAA, no?
No more paper charts?
- Thread starter DaveT
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NOAA maintains the database of all marine data points ( ie: depths, land margins, obstructions etc ) from which it has, in the past, produced those beautiful lithographic printed charts.
The source database is available for use by digital chart providers, as well as POD ( print on demand ) outlets. The Govt will no longer produce the lithographic printed charts. All other producers and their products are unaffected. In fact, I suspect that there will be one or more printers who will offer "the same" product, but simply produced by private enterprise rather than by a government printing press.
In short, the only thing being eliminated is the printing of charts by the government. The field is wide open and all of the raw data used in those paper charts will still be available to "private" suppliers.
The source database is available for use by digital chart providers, as well as POD ( print on demand ) outlets. The Govt will no longer produce the lithographic printed charts. All other producers and their products are unaffected. In fact, I suspect that there will be one or more printers who will offer "the same" product, but simply produced by private enterprise rather than by a government printing press.
In short, the only thing being eliminated is the printing of charts by the government. The field is wide open and all of the raw data used in those paper charts will still be available to "private" suppliers.
Thanks. So how exactly are the charts produced from the data? It's always seemed to me that they are drawn by a human, and are not just a computer rendering of data from a database. Is this not correct? For example, I know that my paper charts look much better than the charts I can view on my Raymarine "E Series" chart plotters. The problem with the "vector" chart plotters is that they never do as good a job of deciding how much detail to include at a given scale than the paper charts do.
- Joined
- Jan 1, 2000
- RO Number
- 3238
- Messages
- 4,831
If I remember correctly, the base data set is quite rich ( ie: dense ), and I suspect that there is a fair amount of "averaging" done to make the currently available electronic charts small enough to be both reasonable from a storage standpoint as well as the amount of computing required to properly display the data. ie most charts that you see are "low resolution" compared to the base database resolution. Electronic systems display the data needed for safe navigation using cost effective hardware. Too much data displayed is actually detrimental to usage. ( it can get cluttered and/or require too long to generate the display ).
There is considerable editing that takes place between the base data and what ends up on your chart chip. ( Thus the same chart from different vendors can look different, while still presenting the required information in an easy to use, near-realtime display using hardware you can afford )
While I believe that there may be some "artistic license" used on the official paper charts I seem to remember that the charts are almost all direct from the database, rather than from the cartographer's imagination. ( I could be wrong on this, but I *think* they are automated, direct from the database... )
In any event, ( at least in the USA ) every official marine chart you can get ( electronic, waterproof, chart book, official paper chart ) is based upon one official electronic data set.
( This is all -from memory- and may contain errors. It has been a while since I did the research on this. )
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here are a few links related to chart production.
http://www.nauticalcharts.noaa.gov/mcd/learnnc_cartogeneral.html
http://www.nauticalcharts.noaa.gov/mcd/learn_diffRNC_ENC.html
There is considerable information available on the subject...
There is considerable editing that takes place between the base data and what ends up on your chart chip. ( Thus the same chart from different vendors can look different, while still presenting the required information in an easy to use, near-realtime display using hardware you can afford )
While I believe that there may be some "artistic license" used on the official paper charts I seem to remember that the charts are almost all direct from the database, rather than from the cartographer's imagination. ( I could be wrong on this, but I *think* they are automated, direct from the database... )
In any event, ( at least in the USA ) every official marine chart you can get ( electronic, waterproof, chart book, official paper chart ) is based upon one official electronic data set.
( This is all -from memory- and may contain errors. It has been a while since I did the research on this. )
--
here are a few links related to chart production.
http://www.nauticalcharts.noaa.gov/mcd/learnnc_cartogeneral.html
http://www.nauticalcharts.noaa.gov/mcd/learn_diffRNC_ENC.html
There is considerable information available on the subject...
