Hi all, I have been following the "nobeltec" discussion with great interest as I make digital maps for a living and I have two PC based nav systems on my boat. This discussion has missed a major point! All of these bells and whistles need the underlying data to work. Remote sense data like aerial photos is rather fast and easy to come by but may not show you the rocks. Credible bathymetry data is another story. For 3D features to be useful the data has to be available at the scale necessary for your use. Data density greater than that provided by noaa is not generally available. If you do a detailed perusal of the raw noaa data you will find that the "point" spacing is based on the intended scale of the finished chart. This standard is a leftover from the days of paper and hand contouring. As an example I was recently doing some bathymetric surface models of the ocean bottom on the west side of san juan island. This is a highly travelled and popular fishing and whale watch area. I was looking to do some habitat modeling for the area in which some people have been monitoring the movement of acoustically tagged fish. There are 4 separate noaa surveys in the area of interest. Even after I stacked these surveys on top of each other the available point density was around 30 meters. Nowhere near good enough for what I needed. There is also the issue of too much stuff on the screen/chart. One of the fine arts of cartography is presenting what is necessary and useful in a graphic manner that makes it rapidly understandable. It is easy to put too much info out there and clutter the display/chart to the point of making it difficult to use. When things are not good and navigation is tense you must be able to see what you need with a brief glance. Overlays of radar, vector data and aerial photography while visually striking are not helpful when things are difficult. When I can buy a multi-beam steerable aperture sonar and process the data in real time, including the removal of backscatter, and display it in the wheelhouse at resolutions of a meter or less for under 10 boat units then nav software will have evolved to the next level of utility. In the meantime vns 4.1.400 and capn 6.1 are what I use with raster charts. The vector chart people do not create their own data they vectorize existing noaa raster data. This process can introduce postion errors. I have not heard of any of the vector chart suppliers advertising their compliance with existing National Map Accuracy Standards. Best, Jim Slocomb M/V Sea Ottter 40' Skookum San Juan Islands, WA --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.456 / Virus Database: 256 - Release Date: 2/18/2003