8.5.3
How to mark school of fish
A detected school of fish can be marked with a "dot" mark for
easy identification.
1. Open the layers menu.
2. Set [Fish School] to [ON] to mark the detected school of fish
with the dot mark.
8.5.4
How to stop advancement of the display
You can stop advancement of the history display to observe the distribution of sea
floor topography and school of fish.
1. Tap the 3D sounder history display to show the pop-up menu.
2. Tap [Pause] to stop the display. To restart the advancement of the history, tap
[Resume] at the top right of the screen.
8.5.5
How to adjust the echo detection level
Adjust the echo detection level if schools of fish are detected unstably.
1. Open the [3D Sounder History] menu.
2. Tap [Fish Detection Level].
3. Select [Low], [Medium] or [High]. The default setting is [Medium]. If too many
schools of fish are being detected, select [Low]. If too few schools are detected,
select [High].
4. Tap the close button on the title bar to finish.
8.5.6
How to calibrate the seabed echo
If schools of fish or a fish reef are detected and displayed as the seabed echo, adjust
the strength of the seabed echo as shown below to correctly identify the seabed echo.
1. Open the [3D Sounder History] menu.
2. Set the correction with the software keyboard or slider bar at [Seabed Echo Cali-
bration]. The setting range is -15 to 15. A large figure helps distinguish bottom fish
from the seabed echo; however, it is difficult to distinguish a fish bed. Use a small
figure to distinguish a fish bed; however, it is difficult to distinguish bottom fish from
the seabed echo.
3. Tap the close button on the title bar to finish.
8.5.7
How to use the noise filter
If the seabed echo is displayed with undulations, use the noise filter to smooth the sea-
bed echo.
1. Open the [3D Sounder History] menu.
2. Tap [Noise Filter].
3. Select [Low], [Medium] or [High]. The default setting is [Medium]. Select [Off] to
stop smoothing.
4. Tap the close button on the title bar to finish.
8. MULTI BEAM SONAR DFF-3D
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