Garmin GPSMAP 580 Owner's Manual page 77

The sonar returns show as red (strongest), then orange (strong),
yellow (medium), green (weaker), and blue (weakest). The Fish
Symbols option allows you to view the actual sonar data, a fish
symbol, or a combination of both. When the unit is set to Dual, the
appearance of the fish symbols changes. Returns from the center of
the beam (200 kHz) display solid (or narrow arches), and returns
from the edges of the beam (50 kHz) display hollow (or wide
arches).
The sonar display can also be set to show a split screen view of a
zoomed portion of the sonar, bottom lock (display scaled from the
bottom up), or a combination of these options. For example, you
can choose to show dual frequency at a 2X zoom (Dual 2X) on one
half and normal range dual frequency (Dual) on the other half. The
current display mode appears at the bottom of each sonar display.
GPSMAP 580/585 Owner's Manual
Adjusting the Sonar Page
Use the Adjustment menu to access the settings and features most
commonly used on the Sonar page. Ten main adjustment options
are available: Range, Zoom, View, Gain, Target Level, Whiteline,
Frequency, Depth Line, Noise Reject, and Scroll. The selected
option appears in the upper-left corner.
To select an adjustment option:
Use one of the following methods to select an adjustment option:
• Press the Rocker right or left to scroll through the adjustment
options. When the adjustment option you want appears,
press Enter.
• Press Menu, highlight Adjustments, and press Enter. Use
the Rocker to highlight the adjustment, and press Enter.
After you select an adjustment option, press the
to change the setting.
You can also press and highlight a shortcut setting to quickly
Menu
change to commonly used settings and values.
Press to accept the new setting (or press
Enter
return to the Sonar Page.
Setting Up and Using Sonar
up or down
Rocker
to cancel) and
Quit
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