wrote in message . com...
The unfortunate reality is that there are too many different
electronic chart formats and a lot of old and incorrect information
floating around. Here's some info I hope is useful:

There are two basic types of charts: raster and vector.

There are two major formats of raster chart and a few minor formats.
Maptech "controls" the BSB format which is the most common of all.
Several companies (such as NDI) produce charts in the BSB format.
Another very popular format is from Softchart (the NOS/GEO format).
All popular software that handles raster charts will handle both of
these formats (exept that Maptech added a copy protection scheme late
last year that some software still cannot handle; these are the "BSB4
Format" charts).

Maptech controls a couple "minor" raster formats as well: PCX and RML;
I'm pretty sure these are basically obsolete and no longer available
for purchase. A few programs still support them, but unless you
already have some it probably doesn't matter.

Another raster format, ARCS, is worth mentioning. These charts are
from the British Admiralty and work with some programs. The licensing
of these charts requires the use of a dongle or other secure copy
protection which is a drawback for many people (even if they don't
want to make illegal copies). Many of the same charts are now
available in the Maptech/BSB4 format.

While the raster chart story is fairly simple, vector charts make
things much more complicated. Most vector charts are proprietary and
any given program or chart plotter will only handle one format (due to
licensing restrictions placed on the software developers by the chart
developers). The only non-proprietary vector chart format is called
S-57 or ENC (Electronic Navigation Chart). This is an international
standard developed by the IMO as an eventual legal replacement for
paper charts on commercial vessels. This is the format that NOAA is
currently producing and giving away on their website free of charge.

The other popular vector chart formats a C-MAP, Navionics, and
Passport. The first two are very popular with dedicated chart plotters
and typically come on little ROM cartridges of various shapes and
sizes. This means that if you want to replace your old chart plotter
but still be able to use your collection of charts, you need to make
sure your new chart plotter can handle the same cartridges. Both of
these chart formats are now available on CD-ROM for use with some
charting software. Passport is Nobeltec's proprietary chart format; it
only works with Nobeltec's software.

Here's a little table listing chart compatibility of the popular
products:

Coastal Explorer - S-57 ENC, Maptech/BSB, Maptech/PCX, Maptech/RML,
Softchart
Nobeltec - Passport, Maptech/BSB (version 3 and lower), Softchart
The Capn - Maptech/BSB, Softchart
Raytech - C-MAP, Maptech/BSB, Softchart
Fugawi - Maptech/BSB, Maptech/PCX, Maptech/RML, Softchart
Fugawi Marine ENC - Adds S-57 ENC to basic Fugawi support
MaxSea - Maptech/BSB, Softchart, ARCS, C-MAP (S-57 on some versions)

I hope this helps!

Brad Christian
Rose Point Navigation Systems, LLC
http://rosepointnav.com/

I do thank you for this most helpful information that was otherwise ,
it seems, unavailable, anywhere. I hope others, who may have been as
confused and frustrated as I was, see this and make use of the
information.