Raymarine E90W User Reference Handbook page 174

• Low (Cruising) is ideal for viewing fishfinder images with a
minimum of background noise as you are cruising to your fishing
spot. Only the strongest echoes are displayed.
• Medium (Trolling) is a slightly higher gain setting that displays
more detail. This is the default mode.
• High (Fishing) provides the most detail, but also displays the
most background noise and surface clutter.
Manual
If necessary you can set the gain controls manually, between a
value of 1 to 100 (default value is 75). This value should be set
high enough to see fish and bottom detail but without too much
background noise. Generally a high gain is used in deep and/or
clear water; a low gain in shallow and/or murky water.
The new values remain set even when you switch off the display,
they are applied to both the active window and any other fishfinder
windows with the same frequency.
Selecting automatic fishfinder gain
From the main fishfinder screen:
1. Press the PRESENTATION softkey.
2. Press the GAIN softkey.
3. Press the GAIN softkey until the AUTO option is selected.
4. Use the trackpad to select the auto mode you want.
5. Press the OK button.
Adjusting the fishfinder gain manually
From the main fishfinder screen:
1. Press the PRESENTATION softkey.
2. Press the GAIN softkey.
3. Press the GAIN softkey until the MAN option is selected.
174
4. Use the rotary control to select the amount of gain you want,
between a value of 1 to 100. (The default value is 75).
5. Press the OK button.
The new values remain set even when you switch off the display,
they are applied to both the active window and any other fishfinder
windows displaying the same frequency.
Fishfinder color gain
You can adjust the color gain to change the signal strength threshold
for the strongest color in your fishfinder display.
Color gain sets the lower limit for the strongest echo color. All
echoes with a signal strength above this value are displayed in the
strongest color. Those with a weaker value are divided equally
between the remaining colors.
• Setting a low value produces wide band for the weakest color, but
a small signal band for the other colors.
• Setting a high value gives a wide band for the strongest color, but
a small signal band for the other colors.
There are two color gain modes:
• Auto. In Auto mode the color gain setting is automatically
adjusted to suit current conditions. Any adjustments made apply
to all fishfinder windows.
• Manual. You can set the color gain manually, between a value
of 1 to 100.
Adjusting the fishfinder color gain
From the main fishfinder screen:
1. Press the PRESENTATION softkey.
2. Press the GAIN softkey.
3. Press the COLOR GAIN softkey until the MAN option is selected.
E-Series Widescreen User reference