Side Scan Fish Posted on August 02, 2016

Finding fish with side imaging is difficult for most anglers since we don’t have enough screens on the boat. We tend to select map, sonar and Down Imaging and forget about the side imaging, but finding fish is easy if you have the right conditions. One of the problems we run into is that a rocky bottom reflects so much of the sonar it’s bright and fish show up as bright areas which means there is little contrast and they are easily hidden, while softer bottoms show up darker so fish really show up in this image.

Notice all the fish on the right on the first image.

I usually leave my unit on 455 kHz since you get much more range than with 800 kHz.

The next image shows larger fish in the red circle and smaller fish in the green circles. Notice the depth is 3.7 ft.

But don’t be fooled by logs on the bottom left over from the timber logging industry.

Yellow arrows are pointing out the logs.

The red circles are around fish which show up as white dots.

The next image has more fish that are longer.  Here we need to remember the length of the fish is dependent on boat speed.  The faster the boat travels the fewer sonar pings that are going to cover the fish so their length will show up shorter.

Another good way for identifying fish is the shadow the fish cast, the farther away the shadow is from the fish the higher in the water column the fish is located.

The red and black circles show fish and shadows. The fish nearer the center are harder to see since the bottom is brighter nearer the center so the shadow becomes helpful in identifying the fish.

Lowrance 3D StructureScan Posted on July 08, 2016

I finally got to play around with the new Lowrance 3D StructureScan and used it to target suspended crappie.
The 3D display works like side can but now you can see where the fish are suspended in the water column. With side scan you can only see the fish are off to the side not where they are in the water column.
This image shows the prop wash bubbles (red circle) and the crappies suspended on the left side (green arrow).

The next image shows the crappies as history as I drive back to them. The red arrows show the prop wash bubbles and the green arrows different schools of crappie. You can rotate the screen to give these different views of the 3D live. So far I have only found it useful for suspended fish but there will be more crappie tacos for me because of this tool.

Understanding DownScan/Down Imaging 2/25/2105 Posted on February 25, 2015

DownScan Interpretation

This explanation is to help explain what you see with down imaging, it is pertinent to all brand’s down imaging.
Down imaging has a wider cone and will show targets off the side better than the 2D sonar (traditional sonar 200 kHz).
Notice the man-made structure plus the rocks.
Sonar tells us the distance to the target. The man-made structure pointed out with the white arrow is 8 feet from the transducer. How about the red arrow? It is pointing at rocks and long strips of something man-made. You can’t tell which side it is on since the left and right edge of the cone is combined, something 12 feet from the transducer on the left with be superimposed on something 12 feet from the transducer on the right side.

If you have side scan you can see which side of the boat a target is.
Notice the rocks are opposite the man-made structure but on the DownScan they are overlapped.

The next example shows fish by a tree on DownScan and the side scan shows the same fish to the left side. The problem is we don’t have enough screens to show all we want. I like to see the map, 2D sonar, down imaging and side scan and that is a lot of dash space to be used. The fish and the tree look like white spots and are hard to interpret.  I like one model with splitscreen sonar and DownScan and one splitscreen map and side scan with the side scan using 2/3 of the screen since wide screens are best for side scan like I used 2/3 for sides can in the image.

Side Scan Fish Speeds 9/3/14 Posted on September 03, 2014

I often get questions on what fish look like on side scan at different speeds from both Humminbird and Lowrance users.

How to Level your StructureScan transducer Posted on July 20, 2013

Knowing how to level out the StructureScan transducer is important for side scan sonar. Notice in this image it is brighter on the right side but does not see as far to the right side. The transducer is not level so the right transducer crystal is shooting more straight down than the left side. This is an easy fix by adjusting the right side a little higher. Remember that the boat is not level when you add two 250 lb anglers on one side and you leveled the transducer for just one person.   I hope this quick piece helps you to understand how to level out StructureScan.

Lowrance StructureScan What We See Posted on July 19, 2013

 Learn how to get the most out of your HDS.