Some of these questions are frequently asked, the others should be!

What is the difference between S-57 and ENC?

ENC (Electronic Navigational Chart) is an application of the wider S-57 vector standard. There are other S-57 'products' although ENC is the most well known one.

This has led to the terms 'S-57' and 'ENC' being used interchangably. Vector and Raster has more information.

How do I use the sample applications?

Using the samples

How does the licensing of charts work? Why do I need a dongle?

Chart Licensing

Where can I get unlicensed (free) ENC data?

There is a lot of unlicensed ENC data about but much of it is for demonstration purposes and not for navigation. But NOAA publish a lot of ENC data free of charge. More info.

Some other sources are mentioned on the Nuno blog.

Free raster charts?

NOAA RNC charts are free although their ENC charts might be better.

NZMariner charts are free.

What projection does ENCX use?

For ENC charts have a look at this this. For raster charts the projection is the same as the equivalent paper chart.

Why don't my overlays line up with the chart?

When overlaying information onto charts drawn by ENCX you need to use the GeoPix class to convert geographical (lat lon) coordinates into pixel coordinates. There are different methods for points, lines and areas (polygons).

Can we use both ENCX for licensed chart data and ENCXUDE for unlicensed data?

Yes. This is quite easily done.

If you have customers with access to unlicensed charts for the waters in which they operate (i.e. the US market) you could ship them software without a dongle. The software uses ENCXUDE.

Later, if they needed to use licensed charts in other parts of the world they could upgrade by buying a dongle and the software would switch to using ENCX to display the charts.

How is ENCX pronounced?

It is up to you. We tend to say either 'E..N..C..X' or 'Encs'.