All mapping companies interpolate map data for certain parts of waters ...
It is basically impossible for a map company to physically map every inch of every body of water on their own map cards ...
Interpolating is "filling in" map data between their own map data points with map data from other sources ... Paper charts, leased map charts, etc ...
I have both Navionics and LakeMaster ...
I find that Navionics is more accurate on some parts of Ky Lake ... While LakeMaster is more accurate on other parts of Ky Lake ...
LakeMaster is more customizable in the HB units than Navionics ...
Rickie