Quote Originally Posted by mduncan62 View Post
Oh prop wash. Guess the Lowrance transducer was mounted further back then the prop?
If you were scanning over prop wash it would show on both sides.
That's not the way it works. Propwash occurs a short distance ahead of the prop as well as behind it. If the transducer is mounted to the left of the motor then the propwash will appear in the right hand view. If the transducer is mounted to the right of the motor the propwash appears in the left hand view. Anyone who has run si can tell you that what you're seeing is propwash. If you just look at the pics I posted earlier you'll see that there are no white interference lines because there isn't any electrical interference and consequently, a much better view of the bottom and structure. The first two pics I posted don't show any propwash because my transducer is mounted off the right side of the boat well ahead of the prop. I retract it when running any faster than 5 mph. In the pic I posted from Humviewer, you can see a steady return about 7 ft deep. That's the left hand pontoon of my boat. Anytime the water is more than 7 ft deep, that left hand pontoon shows up in the image. I'm not sure why this interference issue is so confusing for you. There's no question that the HB was receiving interference that the Lowrance wasn't subject to.