ENC vs RNC...is one better?

[silviris]

So I know the difference between the Raster charts and the vector charts, but aside from the vectors looking a little cartoonish and un-professional, are they any worse than the raster charts? I read somewhere that they were somewhat incomplete, but that may have been an old website. Thoughts and opinions on ENC vs RNC?

[dacust]

Originally Posted by silviris

So I know the difference between the Raster charts and the vector charts, but aside from the vectors looking a little cartoonish and un-professional, are they any worse than the raster charts? I read somewhere that they were somewhat incomplete, but that may have been an old website. Thoughts and opinions on ENC vs RNC?

Here is my take overall about chart errors. In the middle of it I compare raster vs. vector.

==> Inland Waters Resources - Chart Errors

For a small device with limited memory, vector charts take way less memory. Raster charts may take less GPU and CPU to process. Like everything, there are trade-offs.

-dan

[Suijin]

I think it's a largely a matter of preference and how you use your charts, and what device you use them with. ENCs have the benefit of being easily updatable, scalable with faster draw and lower storage requirements, and the ability to turn off different layers. Raster charts show everything, just like paper charts, but take up lots of memory.

I keep both on my laptop, and in general prefer rasters because I think the information is presented more completely and clearly...someone arranged all the information in a way that it could be easily parsed, whereas in RNCs you often get a jumble of indecipherable symbols at certain zoom levels and no heads-up on what is not rendered or included.

I really think the best approach is to download both for the area that you need to navigate and examine them to see which provides you what you need.

[fgd3]

Originally Posted by silviris

So I know the difference between the Raster charts and the vector charts, but aside from the vectors looking a little cartoonish and un-professional, are they any worse than the raster charts? I read somewhere that they were somewhat incomplete, but that may have been an old website. Thoughts and opinions on ENC vs RNC?

At the present time raster charts (RNCs) are superior to vector charts (ENCs) where both are available and contain equally recent data. Both RNCs and ENCs will use those same soundings, even if they are a century old. For US charts, new information is applied to both RNCs and ENCs.

RNCs require more RAM and disk space for storage, but those things are cheap nowadays. Even a cheap netbook has enough storage capacity to handle all the US RNCs (just under 4GB).

(1) RNCs display quicker.
(2) RNCs display the information you need. Cartographers have spent years figuring out what you are going to be interested in seeing when you look at an object on a chart. If the object is an underwater obstruction you want to know how deep it is. If it is a bridge you want to know its vertical clearance.
(3) RNCs look like paper charts. You don't have to learn new symbols or abbreviations.

ENCs are the future of marine cartography. Symbols are being standardized. Chart display programs are getting better at showing important information. Eventually chart display programs will be cognizant of your vessel's draft and the depth of water ahead of you. When you plot a course over a shoal the program will warn you that the water is too shallow for your draft. Already, OpenCPN allows you to customize ENCs, displaying soundings in feet, fathoms, or meters according to your preference and showing deep, shallow, and dangerous water (white, light blue, dark blue) according to your settings for deep, safety, and shallow depths.

Once chart display programs are mature ENCs will be superior to RNCs. Change in the field is rapid, but we're not there yet.

Fabbian