Sonar & Maps

How to read lake contour maps, 2D CHIRP, Down View, Side View, and Forward-Facing Live View—complete with dial-in settings and step-by-step fish-finding image interpretation.

Buying a $3,000 fish finder and only looking at the digital depth number is like buying a smartphone and only using the calculator. Every modern marine graph gives you five distinct eyes underwater: Bathymetric Lake Maps tell you where to drive, Side View scans 30 m (100 ft) left and right to find hidden cover, 2D CHIRP and Down View show what is directly under your hull, and Forward-Facing Live View lets you watch the fish react to your lure like a live video game. Here is how to tune and read every single view.

  1. Contour Lake Mapping & Custom Charting — Before you ever drop the trolling motor, your contour map (等深线水图) eliminates 90% of dead water. Think of contour lines like a topographic mountain map, except going…
  2. 2D Traditional CHIRP & Down View Sonar — Why do anglers often put 2D CHIRP Sonar and Down View (Down Imaging / DownScan / ClearVü) side by side on a split screen? Because each one sees what the other misses…
  3. Side View Sonar Tuning & Structure Identification — Side View (侧扫声呐) is the fastest search tool ever invented. Instead of driving back and forth for hours hoping to run right over a small rock pile, one pass at 6 km/h (4…
  4. Forward-Facing Live Sonar Calibration & Fish Behavior — Forward-Facing Live Sonar (FFS — Garmin LiveScope, Lowrance ActiveTarget, Humminbird MEGA Live) shoots a live vertical fan beam ahead of your bow. Instead of seeing…