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HOW TO DISTINGUISH THE FISH SCHOOL
• Importance is comparison between display of fish school and catch
It is possible to distinguish the fish sort by display of fish school to some extent. But even if fish sort is same,
it’s form making school is different according to difference of fishing ground and difference of time (day and
night, four seasons, variation of current).
The important thing to distinguish the fish sort is to know the sort according to their fishing ground or fishing
period and to find the useful point on the display by comparing between display of fish school and actual
catch.
HOW TO DISTINGUISH THE FISH VOLUME
• Fish volume can be distinguished by density and size of fish school
As the harder density the transmitted wave is reflected strongly, you can distinguish the density of fish
school according to the strength of reflected echo (that is, different color). Normally we tend to think the
larger fish school on the screen the most fish volume. But when fish school are located at the shallow depth
and the deep depth, fish school at the deep depth is displayed bigger than at the shallow depth. Because the
transmitted wave spreads wider as it goes deeper and the reflected wave spreads wider as it goes shal-
lower. As this result, the deeper depth becomes the wider the width of fish school becomes on the screen.
The important thing to distinguish the fish volume is to judge it according to size of fish school and the
strength of reflected echo (color) while you keep “the deeper fish school stays the bigger picture is dis-
played” in your mind.
Reflected
wave
Fish school B
Fish school A
Fish school A picture
(shallow)
Fish school B picture
(deep)
