I have enjoyed (and gotten envious) of the great side scan images. I have a question as I am trying to interpret them. There is a line down the center, I "assume" this is the center of the boat long ways. If that's the truth then why will it have say a 20" to each side other lines. I would interpret this as the width of the boat, however the transducer is below the hull and ought not "see" the hull. So help me interpret this please. I just got the Lowrance hds7 gen3 and boy do I have a lot of learning to do...