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Electronic Charting - by
Arild Jensen
 The number of players in the electronic charting field seems to be getting fewer due
to corporate mergers and consolidations, and there are a few simply disappearing from
view. For example,what happened to Laser Plot? They were big at one time; now I never see
them mentioned.
Recently MAPTECH won the right to be the sole distributor of official NOAA sourced charts
and they also bought out the company which held the patent for the BSB format. The
charting industry has finally settled on BSB as a de facto standard for raster type
charts. MAPTECH has also won the right to distribute the official NOAA vector charts.
These were, until now, used primarily by commercial shipping due to the higher cost and
equipment complexity involved.
MAPTECH must supply the chart data to anyone as part of the agreement to be the official
NOAA distributor.This means that competitive chart program companies can still offer BSB
compatible software products.
In Canada, Nautical Data International (NDI)is the official distributor of CHS digital
data in both raster and vector formats. Since the industry standard is BSB,this is the
normal format used by NDI for distribution of raster charts. Note that all digital data is
copyrighted in both USA and Canada. Illegal copying and distribution has been and will be
prosecuted.
The essential ingredient of any charting software is the ability to depict the vessel's
position accurately on the displayed chart. Anything else is simply window dressing or
"bells and whistles." Most users will likely not enable the additional features
once they get over their initial novelty. This is not to say that these features are not
useful; simply that most people can't be bothered learning how to properly configure the
software. From personal observation, I have concluded that the computer-literate
technophiles will continue to demand more bells and whistles, while the majority of
non-technical users will want a simple box that they turn on and watch, much like they use
a depth sounder.
What all of the programs have in common is the ability to increase the navigator's
situational awareness due to the continuous update in plotting and display of the vessel's
position relative to the shore and underwater hazards.
One Canadian program, FUGAWI, costs $130 and does as good a job on the basic essentials as
the most expensive. If you don't use the features why pay the extra money? There are even
a few shareware programs which seem to run well and are free of bugs.
VECTOR CHARTS
Currently, both C-MAP and Navionics offer a low level vector type chart which is sold
along with dedicated chart plotters from a number of manufacturers. Their chief advantage
is the splashproof packaging of the display box, simplicity of use, and an easier learning
curve. The downside is lack of full detail as compared to either the paper chart or
electronic raster charts.
One additional problem with vector charts is the internal process used to drive the
display.
Each displayed object is defined by its coordinates. The equipment manufacturer must
develop suitable interface software to correctly interpret this vector data and generate
an appropriate display. Garmin displays nav aids differently than Raytheon or Northstar,
to name a couple of brands. Garmin's color display looks different than their own
monochrome display, even when using the same chart chip.
An additional problem for Canadian users is the fact that ome of our cruising grounds are
not adequately covered by either company. In the global scheme of things, Canada is not a
big market.
The more complex vector charts distributed by NDI and MAPTECH will have the same problems
and attendant cost attached, regardless of who the equipment manufacturer is.
The only official data format standard is the IMO S-57 standard which defines how and what
is shown on vector charts. At present most commercial systems use UNIX based computers or
similarly complex dedicated software in order to handle the data processing. Until
recently this was beyond the cost factor of consumer oriented products.
While it is true that new software enhancements are continually being announced, they do
not add to the accuracy of position plotting and it remains to be seen whether they are
simply novelty features or real benefits.
For example, Nobeltec offers "quilting", which seamlessly merges adjacent charts
even if at different scales.
Maptech offers arial photography which is displayed at the same scale as their NOAA charts
in a split screen mode so you can see the chart and the arial view side by side.
CAP'N offers a radar overlay so you can merge a radar image with the chart. That is useful
but also very expensive.
Raytheon and Furuno provides the reverse. They can display their vector C-MAP right on the
radar screen but not overlaid with the radar. You can have either/or or a window insert
map within the radar image.
There is no doubt that the industry is still growing and developing. Leading edge products
still cost nearly $1000, taxes included, and the computer is extra. Comparable vector
displays of similar size are in the same price range. However, chart display capability is
becoming available in more and more low end products, costing only a couple of hundred
dollars. Right now you can buy a GPS receiver with basic chart display for about the same
as a large display graphic depth sounder.
The ultimate electronic display has not been built yet. That would be a three dimentional
holographic display with the vessel seeming to "fly" above the seafloor and
around obstacles with the water being completely transparent and the depth scale
compressed suitably for ease of perception by the observer.
I have seen these displays in crude form as experimental prototypes at hydrographic
conferences but these will not become available untilthe seafloor has been mapped 100% by
swathe type sonar,a process that will take several decades. Then someone will have to
develop a commercially viable holographic display.
Meanwhile, we do have some neat software to play with. You pays your money and takes your
chances. You can have the basic utility for $100 or the sky's the limit, depending on how
much you want to play and pay.
Arild Jensen The Electronic Navigator
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