Garmin GPSMap 498 Owner's Manual - Page 92

USING SONAR > FLASHER PAGE Flasher Page The Flasher page provides an almost instantaneous return of what is below your boat. This page can show depth, fish, bottom content, and structure. When you use the Flasher page, you can adjust the Range, Gain, Color Gain, Frequency, and Scroll settings. See page 79 for information about these settings and how to change them. Flasher Page Understanding the Flasher Page The most intense, constant signal on the Flasher Page is the actual depth and bottom: • A soft bottom (such as silt or mud) creates a signal that is narrow and more faint. • A hard bottom (such as sand or rock) creates a signal that is wider. The colors indicate the different strengths of the signals. If you understand a bit about how sonar works, you can better understand what you see on the Flasher Page. Remember, three-dimensional space is appearing on a two-dimensional screen. The circular area of the bottom becomes a wide mark on the screen and fish inside the transducer beam can be any color and in any position, including inside and beyond the bottom mark. The colors indicate the different strengths of the signals. This can be roughly correlated to a position inside the beam. Red being the center most part, orange the area around, and green the outer edge of the beam. Targets (for example, fish) with larger surface area appear more red; and targets with less surface area appear orange, and green for the smallest items. 84 GPSMAP 392/398/492/498 Owner's Manual