This picture was taken while driving 18.6mph. It is a good example of how well Lowrance Structure Scan works, even at higher speeds. The sonar on the left side of the page shows a 5 foot hump with 20 foot water nearby. There is a vertical white line that is barely seen at the top of the hump. The upper right picture is side scan shooting out 80 feet to the left and right side of the boat. In the middle of the picture you may notice an hour glass shape that turns bright yellow with a horizontal line in the middle of it. [The brighter the yellow the harder the bottom] The bottom right of the screen is downscan. It also shows the depths very clearly and picks up this 'mystery' line at the top of the hump. It also shows a fish 18 feet deep on the right side of the picture just before the bottom starts back up again. The 'mystery' line is actually an underground silo with a concrete bottom. Notice in the downscan pic the yellow line extending down under the water portion of the silo. [ an underground silo is where a farmer digs out a huge trough into a hill where he stores his silage for the winter then puts a cover on top of it to keep it dry.]
There are two sections to this screen, the left side is bottom lock. It it locked onto the bottom regardless of the depth and is reading 2,4,6,8 feet up off the bottom. It actually is set to show the bottom portion of my screen zoomed in three times larger than the sonar on the right side of the screen. Those arches are Stripers stacked right on the bottom of the lake.
This picture is a sonar page showing a group of Stripers that are streaking [active] up on the flat and another group of Stripers out over the channel. The fish on the flat are catchable, the fish over the channel are inactive and will not feed.
The upper sonar picture is a classic feeding scenario for Stripers. They are on a flat looking to eat. The larger lines at 20 feet are the Stripers and above them are 10 inch gizzards.
The bottom picture is an area of the lake stacked with probably millions of Gizzard Shad. Notice in the top portion of the screen in my history that I had been marking the schools for a couple hundred yards. Think the fish have enough to eat?