Furuno CSH-5 MARK-2 - Manual (Page 33)

27
Fish School
A fish school appears as a mass of echoes on the screen. The color of
the mass shows the density of fish schools on the sonar beam. To
know the distribution and center point of a fish school, the tilt should
be changed to several different angles.
Sea Surface
Reflections
Fish
school
(a) Sea Surface Fish
Tilt Angle: +5
°
- 10
°
Because of
the narrow
tilt angle,
seabed
echo is not
displayed.
Sea surface
reflections
are present.
Fish school
Seabed
(b) Midwater, Bottom Fish
Fish echo appears before seabed echo
Tilt Angle: 30
°
or more
Large midwater
fish school is
present.
Fish School
Seabed
Fish echo appears together with
or after seabed echo
Tilt Angle: 0
°
- 20
°
Since the seabed is displayed in weak echo colors,
longer range detection and detection of close to
bottom fish school become possible.