How to create underwater terrain map with fish finder

Today, we came to the island of latitude in Buan-gun to make a map of sea bottom land using Dipper Pro Plus. I started to draw the map at the point where the mainstream is flowing far away from the front and leisure is stretching around in the water. The water depth varied from 1m to 8m. Among them, I was able to identify meat in a complex terrain, a dented place, and a protruding place.