Understanding The Down Imaging® Display; Interpreting The Display - Humminbird 1100 Series Operation Manual

Interpreting the Display

Down Imaging® beams "illuminate" the bottom contour, structure, and fish. The beams are wide
(side to side) but very thin front to back.
Use the light and dark parts of the display to interpret the objects under your boat as follows:
• Dark shades represent soft returns (mud, sand) or descending terrain.
• Light shades represent denser terrain (timber, rocks) or rising terrain. A very hard
bottom may appear as white on the display.
• White Streaks or Clouds may represent fish on the display.
• Shadows are not caused by light but by the lack of a sonar return. Objects standing on
the bottom cause a sonar shadow to appear on the display. The longer the shadow, the
taller the object. Fish may also cast shadows. You can use the shadow to interpret where
the fish or object is located in relation to the bottom.
What's on the Down Imaging® Display
Understanding the Down Imaging® Display
The images you see on the Down Imaging® display are
produced using sonar technology. Each time the unit pings, a
strip of data representing all the echoes received by the
transducer are put together on the display to form the image
that you see. Like traditional 2D Sonar, the sonar history scrolls
left across the screen.
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