I've been using GPS NavX for several years for planning my trips. I've been using raster charts downloaded from NOAA. The NOAA web site describes raster navigational charts (RNCs) as "…full-color digital images of NOAA paper charts". And when I'm looking at a chart for my area my depth units is listed as "fathoms and feet" just as it would be displayed on the paper version of the chart. On my chart plotter, I believe that I can choose and change the depth unit setting for the chart, and not just for the depth sounder (unconfirmed at this point). I'd be seriously impressed with a system that could read and convert raster chart depth data on demand. On the other hand, if it were a vector chart, I'd think that conversion on the fly would not only be possible, but expected.
Now that I've become accustomed to using NOAA paper (electronic raster) charts for my planning, I don't seem to care much for the appearance of the vector charts when I select them from my new chart plotter. Without the land mass topo contours, I feel like I'm missing something. Now that I know what I'm missing, perhaps I'll become more comfortable with the all digital format...
