What’s on the Down Imaging Display
18
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.
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.
18
Summary of Contents for HELIX 5 DI
Page 1: ......
Page 6: ......
Page 49: ...Sonar Menu Normal Mode HELIX DI Sonar Menu Advanced Mode HELIX DI 43 Main Menu...
