
Originally Posted by
rnvinc
For SI and DI Chart speed matching boat speed gives the best results ... This is simply because the Sonar beams in SI and DI are very thin front to back ...so the ratio of data collected in a single imaging sound pulse ("Ping") equates to the measure of forward travel in the boat ... (think of how a MRI takes slice pictures of the human body and then "stacks" them back together to make a "whole body" picture) ...
2d Chart speed is a different animal and should be maxed out to get the echoes to "stretch" across the 2d display ...
Rickie