the Perspective sonar view, select Menu > Sonar Setup > Appearance.

Color Scheme

Sets the color palette.

Color Gain

Adjusts the intensity of colors shown on the screen.

You can select a higher color gain value to see targets higher in the water column. A higher color gain value also allow you to differentiate low intensity returns higher in the water column, but this causes a loss in the differentiation of the returns at the bottom. You can select a lower color gain value when targets are near the bottom, to help you distinguish between targets and high intensity returns such as sand, rock, and mud.

Trails

Sets the how long the trails appear on the screen. The trails show the movement of the target.

Grid Overlay

Shows or hides grids of range lines. The Grid option shows a square grid. The Radial option shows a circular grid with radial angle lines.

Boat Icon

Shows the icon of the boat in the upper-right corner.