Check this thread out & specifically the chart/picture I posted : http://www.crappie.com/crappie/side-...dsi-questions/
2d is a cone shaped sonar ping
DI is a narrow fan shaped sonar ping
Both register the image as X number of feet "deep" ... when, in reality, X number of feet is a measurement of distance from the transducer to the object, regardless of where it is within the cone or fan shaped sonar ping.
This chart may help, also, as it shows the different shapes and dimensions of each sonar beam type:
http://i1057.photobucket.com/albums/...ps5d77b127.png
... cp :kewl

