Educational Articles » lowrance

Catching Side Scan fish Posted on August 01, 2018

Catching fish you see on side scan is tough since they can move before you get to them but I have a great example.

I was fishing for walleye with spinners, worms and a bottom bouncer in the weeds. I thought I saw the jackpot in the red circle. I moved the cursor over to the fish and created a waypoint on them. The green arrows point out the weeds.

side scan white bass

I then trolled through the waypoint in about 1 minute and caught a white bass. Not what I wanted since I was hunting walleyes for an upcoming tournament but a nice example of how to use side scan.

white bass





by Bruce Samson under lowrance lowrance sidescan

Fish or weeds? Posted on July 15, 2018

Just another example on why down imaging helps sonar interpretation. The weeds look similar to fish.

Weeds or fish 1

 In this one the fish look like weeds.

weeds or fish 2

Airmar TM150 setup Posted on May 28, 2018

If you use the Airmar TM 150 on a Lowrance I have found the Custom setting of single frequency 105 kHz gives me the best results. However you need to turn off the noise rejection to get those results.

The left side of this image has the default setting of Noise Rejection set at low and the right side is the Noise Rejection turned off. I don't know why this transducer doesn't perform well with the Noise Rejection on.

Lowrance TM 150 settings

Understanding unusual side imaging images Posted on May 08, 2018

Warren Parson captured some great video of flooded structure on Devils Lake with his Aqua-Vu HD camera

Watch tutorial

Devils Lake side imaging

Lowrance Hook2 Review Posted on January 10, 2018

This review is done by Mark O'Neill Doctor Sonar Pro Staff

Lowrance first introduced the touch screen family of products to the fishing industry in 2012.  While the touch screen does open doors for ease of operations that can be achieved by a single touch of the

screen as opposed using a cursor and clicking on various keys to achieve the same results, touch screens are expensive and that leads to higher costing units. With the new Lowrance Hook2, which is being labeled as the easiest-to-to use fish-finder, a similar interface as the HDS Touch/Gen 3/Carbon units has been incorporated, but without the touch screen. This leads to very easy to use operations where one incorporates the use of the cursor as opposed to just the touch screen to choose the desired function.

Lowrance Hook2

Additionally, the new Hook2 series has gone to a wider screen format on all models starting with the value priced Hook2-4X all the way up to the top end Hook2-12, which enables the user to now have more viewable screen area, which is especially nice when having three screens showing vertically at once.

Hook2 sonar menu

For those that want a unit where one simply has to turn it on and fish, then this may be the unit for you. But there is much more to this unit than that if one desires. There are three different sonar modes, Au- to, Custom and then Ice Fishing. When run in Auto mode, the sonar will operated in the high chirp frequency and all functions are fully automatic. If one desires to make some adjustments or to change to 200 kHz, one simply changes to Custom mode and you have full adjustability. For those that ice fish, the Ice Fishing mode will enable another independent set of options that can be set and retained just for ice fishing, which I have to admit makes this a very attractive versatile device.


For most anglers the Auto mode will work just fine as the sonar cone angle has been increased to 44 degrees, which is about two times the range of most common sonars. So what does that mean for your average angler, the ability to see more fish.

Hook2 cone size

Lowrance Provided Image

There are a number of different model choices to choose from, ranging from the very affordable Hook2-

4x to the top of the line Hook2-12 Combo. While the Hook2 is being targeted at the low-mid level tier product segment, the features available are very impressive with three different transducer options will be offered, the Bullet, SplitShot and TripleShot.

Hook2 transducers

Lowrance Provided Images

In addition to sonar, Down and SideScan options, there are also GPS options that the consumer can choose between. Models choices range from sonar with GPS plotter (no mapping, but does include the ability to save and use waypoints and trails), and then combo units that add full GPS Mapping (micro SD slot for upgraded mapping and software updates.

The connectors, both transducer and power have changed from the traditional screw locking types used on the older Hook models to a press fit O-ring sealed style. The fit is a tight and seals well, so I do not see this as an issue.

Hook2 power cable

Lowrance Provided Image

So as with any fish-finder, the bottom line is performance.  One can taunt all the features one wants, but if the unit doesn’t perform, those features are meaningless.  The Hook2 brings in new life to the Hook family of products as compared to its predecessor.  In fact the Hook2 has very little in common with the previous generation of Hook models. The interface for the Hook2 is much simpler to operate, the

screen image is much clearer and the processor is lightning fast  as compared to the original Hook models.


As far as performance on the water, the Hook2 performed extremely well. As stated, the sonar, DownScan and SideScan functions have an “auto” mode which enables the user to simply fish and not have to worry about fine tuning settings. For more the more advanced user, one does have the ability

to customize the settings if one so desires. Running the sonar and DownScan in auto, I had no issue seeing baitfish, predators and even my own bait while fishing.

Hook2 sonar


Another nice change for the Hook2 is with mounting system of the units themselves, the 4 and 5 inch displays now incorporate a very well thought out base that is very solid and yet the unit can be easily removed when needed.  This replaces the former Hook base for the smaller units which proved to be difficult at times or some end users.

Hook2 mount


The Hook2 product line will be a winner in my book, it definitely fills all voids that the earlier Hook versions had and then adds simplicity and more capabilities. With a range of 12 different configurations available in varied price ranges, there is a model for everyone based on their needs. Although designed for the entry to mid-level end user, anyone on the water will find value with this product.

HOOK2 Training DVD

Mark O’Neill

Doctor Sonar Pro Staff

by Bruce Samson under lowrance product reviews

Fish size on sonar Posted on October 30, 2017

Identifying fish size on sonar is very difficult since you can change the size with sensitivity adjustments or depth range. Fish look larger on a depth range of 20 foot than 100 foot. The size of a fish is determined by the color of the fish arch. For example if you have palette colors yellow, blue and red. The more yellow you see the bigger the fish. The thickness of the fish arch also determines fish size. How long the fish arch is just how long the fish is below the transducer.

In the image the black vertical lines show how long the fish is under the transducer and the green lines show the thickness of the fish arch.

fish arch

The best way to tell size is catch one the fish you see on sonar or use an Aqua-Vu camera.

The first example shows my bait dropping (green arrow), the bait is intercepted by a bass (red arrow) and the bass swims to the bottom (black arrow) and then I set the hook and catch him.


This is the bass.

large bass on sonar

How about these fish. Needless to say I was excited when I found them but they didn't bite so I dropped the Aqua-Vu camera and was surprised what I found.

carp on sonarcarp on sonar 2

Watch video of fish

 On this screenshot is a 7.5 lb. northern pike, you can see when I set the hook and started bringing him to the surface.

Northern pike for sonar size educationnorthern pike

The last screenshot is smallmouth bass and I caught a few, this is a picture of one of them. One of my favorite fish to catch.

smallmouth basssmallmouth bass

This screenshot shows a 29.5 inch walleye after being released.

29 inch walleye29 inch walleye

I was lucky in my timing to collect good data to prove fish size on sonar.

Last but not least is what a 5 inch minnow attached to a sinker looks like with 1.5-2.5 lb. walleyes below it.

walleye and minnow size on sonar


GPS Accuracy Posted on August 26, 2017

Ever wonder why your big boulder is in a different place than your waypoint at times? GPS can more accurate one day depending on satellites and weather and where your fish.

The boat is at my dock and I cleared the trail after the GPS locked in really good. This example is normal, I have repeated it many times and this was one of the most accurate examples. I did this one with Lowrance's point 1 GPS.

Your big boulder could move 25 feet on you while you were fishing it!

GPS Accuracy

by Bruce Samson under lowrance lowrance gps

StructureMap another method Posted on May 01, 2017

StructureMap is available on the HDS and Carbon but you can share it with the Hook!
If you have logged sonar with a model with side scan you can open it in ReefMaster and export it as map. Think about the value for trolling or anchoring on key structure when the image is your map.
The first image is zoomed out and the 2nd image is zoomed as far as I can with the Hook. Notice the 20 foot scale in the lower right corner for reference.
Since I didn’t have my StructureScan 3d transducer yet I used the Helix Mega to get the side scans. As you can see the MEGA imaging is very crisp.
ReefMaster works with both Lowrance and Humminbird.

If you find tech easy this is a good way to use Spot/Anchor Lock on your favorite reef spot.

3D StructureScan Training Posted on March 14, 2017

Short video on how to use the 3D StructureScan and how to adjust the features and settings.

Watch Video

Lowrance StrucureScan 3D training examples Posted on March 09, 2017

Author Kirt Hedquist Doctor Sonar Pro Staff

The orange dots are fish, the blue triangle is the area of the water column viewed by the sonar. The brown is the bottom of the lake.

I was mowing the grass doing some scouting you can see some bait fish probably suspended where I started my pass. red circle

To the left of the boat is dropping off to deeper water and shallow to the right (notice how the blue triangle slopes down)

Also note more bait fish just to the right (green circle)

Covering about 360’ in width off to the left and behind the boat you can see a transition to harder bottom as its getting deeper. Red circle

 Some fish below and behind the boat the cluster on the left and below maybe some turbulence. Green circle on fish

To the right its getting shallower with a little hump to the right and below the boat. Orange circle

Some fish and baitfish suspended in the water column dropping off to deeper water to the left of the boat. drop-off red circle

The edge of some rocks or rock ridge to the right of the boat. Green circle

Showing some fish and baitfish in the water column deeper to the left getting shallow to the right Red circle on fish, green circle on shallow area 

A large amount of bait fish (red circle) and a ridge or rock pile (green circle)

Lots of Smelt in this lake, fish are well fed 

More of the same lots bait, a transition from soft to hard with a ridge or rock ridge to the right (red circle)

Shallow water on the left and a drop off to the right 

by Bruce Samson under lowrance