Short video on how to use the 3D StructureScan and how to adjust the features and settings.
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
I produced this short video using sonar, down imaging and an Aqua-Vu to show you how I interpret sonar.
Click on image to view video
The first 2 discussions will be my pro staff reviews and the last discussion will be Doctor Sonar's suggestions for interpretation and settings.
Mark O'Neill review
Kirt Hedquist review
Doctor Sonar 3D StructureScan training
It’s that time of the year, many are getting a new boat with electronics or are outfitting an existing boat with new electronics. Here are some things to think about when looking at purchasing new electronics. Use this as a checklist to help you make a educated decision.
And a few install tips are also thrown in.
- What is your budget?
- Prices range from 100.00 up to the sky is the limit.
- Get the biggest screen you can afford. A common comment at shows is “I wish I would purchased a bigger sonar screen when I bought my boat last year”. Many dealers will throw in 3” screen and you think oh boy a sonar and GPS! After you become experienced with the boat that 3” screen will not cut it. 7” screen size minimum size IMHO.
- What kind of boat?
- Tiller or console? This can affect what units will be right for your situation and you may save some money.
- How much room or clearance do you have to mount a unit?
- If you have a walk thru windshield you may not be able to fit a 12” screen like a tiller or side console.
- What do you have currently on your boat?
- Maybe you can repurpose this to another location or 2nd unit to serve as the GPS/Map screen or a bow unit.
- The 2 networking systems are-
- Ethernet (High speed data transfer, sharing screens, maps, waypoint management)
- NMEA 2000 (Data transfer, monitoring engine data, GPS modules, trolling motor control)
- Not all sonars have these capabilities.
- Do you own a Smart Phone or Flip Phone? The old keypad sonar technologies are similar to operating a Flip Phone! Try a touch screen sonar like the Elite Ti and Gen units and you will note how fast they are to navigate around the screen and menus. You will be amazed! And yes Lowrance work cold or wet unlike a smart phone. Go find a flip phone and try and text someone you will be looking for your smartphone right away. And the prices on the touch screen units such as the Elite Ti starting at 499.00 and up.
- Do you plan on networking to another sonar now or in the future?
- If you plan on just having a single unit now and forever why spend the extra money on units that have the networking capabilities? Example Lowrance Elite Ti without networking –vs.- HDS Gen units with networking capabilities or some Humminbird Helix Gen 1 models vs. the Gen 2 models.
- If you are buying a tiller and never plan on networking to another unit get a unit like the Elite Ti, Hook or Gen 1 Helix without Ethernet and you can spend the extra money saved for a bigger screen
- If have a console boat and plan on networking to another unit on the bow or in the future get a unit such as the Helix Gen 2 series or HDS with Ethernet so you can hook to another Gen unit and share data back and forth. Why waste the money on a non-networkable unit now then only to add another unit to the bow later and lose out on the networking bonuses.
- Do some research on how the networking works.
- Is the unit mounted in such away that the built in GPS module will be obstructed from the sky and satellite’s?
- You may need an external antenna to get a signal.
- If you fish slow or like to cast a heading sensor like the Lowrance Point-1 or Humminbird AS GPS HS will greatly assist in boat control and fishing by always showing which way the front of the boat is facing.
- The internal GPS antennas are excellent but do show which way the boat is facing until you start moving forward.
- Look at incorporating the latest sonar technologies such as-
- DownScan/Down Imaging
- SideScan/Side Imaging
- Chirp Sonar
- Bowmount trolling motor control? Many types of sonar can control a trolling motor and steer the boat with an autopilot feature or route programmed into the sonar. Anchor mode/Spot Lock saves your back or your partner will thank you for not having to pull an anchor.
- Do you troll with the main motor or kicker? Add an autopilot feature that will steer your boat while you fish. It will keep your boat on a course while you are reeling in and netting fish or deploying lines.
- If you are unsure about installing a system utilize reputable installer. It will make your time on the water much more enjoyable when it all works correctly.
- Getting the transducer at the correct placement can be a trial and error task to get a good signal at high speed.
- Use a plastic transducer board to mount transducers. It’s easier to drill more holes in the board than your boat if you make a transducer location mistake.
- Make sure to add a mapping card with more details. Units come with base mapping and it’s just that 3’ to 6’ contours or just a lake outline. Cards from companies like Navionics, Lowrance and LakeMaster give 1’ contours on many lakes that will enhance your fishing experience and save your lower unit from a date with a rock.
- Don’t use wimpy sonar mounts! Bigger is better that 9” sonar mounted on a 1” ball mount will be slapping against the dash on the first big wave!
- Many of the new outboards can be connected to sonars and get engine data right on the sonar screen. Doing away with expensive and antiquated dash mounted gauges.
- More and more units can do live mapping on the screen. Lowrance recently incorporated Navionics SonarChart Live into the Elite Ti, Gen 3 and Carbon units, Humminbird Helix models have AutoChart Live, and Garmin has Quickdraw. You can make your own map of bodies of water with no maps or poor mapping.
- Batteries don’t skimp here! Get the biggest starting battery you can or a second house battery for electronics they draw a fair amount of power and stranded on the lake with a dead battery is a bummer.
- A good house battery is the Optima D31M. Doc and his pro staff mark O’Neill and Kirt Hedquist use them because bigger is better.
- And also use Optima D31M for the trolling motor batteries.
- Go to com and follow Doctor Sonar on Facebook and read the tutorial articles on understanding sonar.
Sorry, but it doesn’t work well. We can only make educated guesses.
I was looking for walleyes in the fall and noticed these nice fish at the depth I fish plus they were close to the bottom which is typical for walleyes.
But you bass anglers should read this tutorial so you can catch more fish.
I used small minnows and didn’t get bit so I up-sized to giant chubs (7 inches) and bass anglers know how much smallmouth love big minnows and I got bit. My Go Pro works well for selfies.
I decided to put down the camera to see if any walleye were mixed in and nope, just lots of bass. So, I smoked them and released them so someone else can have the same pleasure.
Watch Video of the fish
Just another reminder to not speed down the lake to the "next hotspot". I usually keep the boat at 20-24 mph and pay attention to the sonar because fish will show up in places that I don't suspect. Rule of thumb for walleyes is they don't follow the rules.
I was traveling at about 22 mph when these fish showed up on a drop and slowed to 3.7 mph. Notice the cursor is on the fish. I marked a waypoint and caught supper. I caught the walleye near the bottom and I am not sure what the suspended fish were since they didn't bite. They could have been walleye.
Understanding bottom hardness is vital to understanding and catching walleyes.
Sometimes it is easy like this image with the hard bottom on the left.
I use Auto-sensitivity on my Humminbird and Lowrance models almost always. It works so well we never notice when it adjusts. Auto-Sensitivity mainly adjusts for depth. We need a higher sensitivity in deeper water since the sound that returns as you go deeper becomes weaker. A manual setting of sensitivity for 10 feet to get the optimal image would not show fish at 100 feet and this is where Auto-Sensitivity shines.
I’ll use examples from this summer when there were a lot of microorganisms in the water so you see a funny screen to help understand what is happening when the auto-sensitivity is working.
The first image shows rapid depth changes at a speed of 30 mph. Notice the clutter clears when I go shallow (green arrows).
The next image shows the suspended clutter change as I go up the slope. At the same time as the clutter changes, the bottom changes (green arrow). The Auto-Sensitivity has decreased the sensitivity at a certain depth. It is important to understand this when you are trying to determine bottom hardness as walleyes are often found by finding hard bottom.
The 3rd image shows what appears to be harder bottom on the right side of the image but this is caused mainly by the Auto-Sensitivity increasing the sensitivity as I go deeper (green arrow).
Harder bottom has a wider bottom band and stronger colors like the yellow. It is easily to fooled by this image and think there is a transition from soft to hard bottom which walleyes often prefer.
Auto-Sensitivity is a great feature but understanding its limitations is important for hunting hard bottom which can result in you greasing the pan for walleye more often.
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.
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.