Furuno SFD-1010 Operator's Manual page 167

Settings
The following settings are available.
Common items with [Bottom Depth Shading Setting] and [Fish Depth Shading Setting]
Item
[Auto] Automatically set the depth to display with the shading.
When [Auto] is [On]
[From] Use the slider bar to set the shallowest depth to start shading.
[Auto] must be [On] to set the depth. Press the MENU/ESC key
after setting.
[From], Shallowest depth
4. MULTI BEAM SONAR DFF-3D
Description
When [Auto] is [Off]
Setting
range
(option)
[On], [Off]
0 ～ 1200
m
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