Side imaging

The original design and purpose of sonar hasn’t changed much, despite the growing tide of newer sonar units that offer side imaging, structure scan and even down scan.

What has changed is the way these units use the basic principal to read and interpret the data based upon which direction the transducer is pointed.

At the heart of side-image technology is a unique transducer that sends sonar signals to the side as well as downward. Hard structure such as rocks or bridge pilings are easier to identify on the screen, providing the user a clearer picture of objects that lie below and out to the side of the boat.

Side imaging is often related as viewing a black-and white photograph.

Another impressive feature of side imaging is the ability to mark a waypoint out to the side as the boat passes it, allowing you to later return to that spot and fish it.

Traditional sonar, which from this point forward will probably have to be referred to as “down imaging” or “vertical sonar” because of the rising popularity of side units, will display the same bottom features as a side image. But in order to read down, the transducer has to be over the top of the structure being graphed.

By using side-imaging technology, the angler maintains the advantage of not spooking fish because he is not disturbing the immediate area with the presence and shadow of the boat.

Also, more of the bottom area can be graphed because you don’t have to place it immediately under the boat to do so.

In addition to the side-imaging feature, these units provide traditional down-looking sonar from a separate transducer, as well as excellent detail and information on the same screen.

You can even set up your screen so that you are looking at side imaging and traditional down-looking sonar simultaneously.

Learning to read and interpret side imaging has its challenges; of course, so does reading vertical sonar. For instance, softer-profile items like grass or smaller timber may appear as shadows. Bear in mind that even hard targets will look like photographs laid on their side.

Visit www.humminbird.com to learn more about side-imaging sonar.