the way to go

SLV Example Image 2

Notice the gradually decreasing sensitivity of the record as it is played back on the Sonar Viewer. The large reddish objects are schools of fish off the coast of Santa Catalina Island.
 
Santa Catalina record sensitivity adjusted 1 Santa Catalina record sensitivity adjusted 2
Santa Catalina record sensitivity adjusted 3 Santa Catalina record sensitivity adjusted 4
EPiTrace logger