Five marine electronics brands offer side-looking sonar: Garmin, Humminbird, Lowrance, Raymarine and Simrad. I’ve found each useful for quickly finding schools of bait, reefs and wrecks — elements that attract game fish.
Side-looking sonar covers a lot of water. StructureScan HD SideScan in the Lowrance HDS Gen3 (featured above) covers up to 300 feet on either side of the boat. Raymarine’s CP200 CHIRP SideVision Sonar covers up to 600 feet on each side, and Garmin’s CHIRP SideVü blasts out 750 feet abeam of the boat with the proper transducer, covering a swath of 1,500 feet — that adds up to five football fields.
Side-looking images appear almost lifelike, making it easy to recognize objects such as wrecks or rock piles, though bait schools appear as a group of small, light dots. Like a medical ultrasound’s, all images are produced in shades of a single hue.