A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: John Brown
Date: 2016 Feb 12, 10:54 -0800
Frank, I hope I'm not taking this out of context:
All contours deeper than 50 meters, and possibly shallower, should be disabled. They are completely irrelevant to a surface navigator.
Seamounts rising steeply from an oceanic abyssal plain, with a charted depth of around 50 metres are often the location of very heavy and/or confused sea and swell conditions.
Also many, if not most of these seamounts have not had an accurate depth survey for decades, if ever. Their whereabouts should certainly be of interest to the surface navigator.