02-26-17, 11:58 AM
Dragonfly 7" fish about 20 inches long from sonar image?
I captured this fish lying on the lake bottom of 8 feet deep with my dragonfly 7 chirp fishfinder. I zoomed into water column between 4 feet and 8 feet. The fish is taking about 25% of the screen. I know my sonar covers 5 feet diameter circle cone for every 3 feet of water.
Am I correct about my calculation of the fish size?
25%*(8-4)*5/3=1.67 feet or 20 inches?
I captured this fish lying on the lake bottom of 8 feet deep with my dragonfly 7 chirp fishfinder. I zoomed into water column between 4 feet and 8 feet. The fish is taking about 25% of the screen. I know my sonar covers 5 feet diameter circle cone for every 3 feet of water.
Am I correct about my calculation of the fish size?
25%*(8-4)*5/3=1.67 feet or 20 inches?