How to Identify Fish and Structure on Side Imaging

Mark Courts breaks down the basics on how to use side imaging.

The benefit of side imaging is that it allows for much greater coverage than that of 2D sonar. For example, instead of seeing 10 to 15 feet with 2D sonar (depending on depth), side imaging gives the user the ability to show a much further view (for example 100 feet on each side in this video). The key to benefiting from this extended view is to learn how to identify relevant structure and fish.

For example the darker color on side imaging indicates a softer bottom. When looking further to the sides (such as in the beginning of this video) the image darkens up and any hard return (small bright spots) in that darker zone are likely fish.

However, as the return on the bottom brightens up it indicates that the bottom has become harder – and often times features such as gravel begin to become apparent. In these situations with a lot of structure, such as boulders, fish can be more difficult to pick out. However, something to know is that if they’re up in the water column, they’ll be easier to spot as clear arcs with matching shadows. Mark explains that the key to identifying this as well as the size of boulders is to analyze the shadows. To do this, be sure to zoom in on the graph.

Finally be sure to mark any particular boulders or fish. Do this by moving the cursor to the spot and hitting the “mark” button to drop the waypoint. Then it makes it easy to swing around it and target that individual fish or structure.

In summary, Mark emphasizes the need to not get frustrated by electronics. Instead go out and practice, and make a few minor adjustments each time. Remember, learning electronics gets easier each time you hit the water.