Educational Articles » humminbird down imaging

Understanding Fish on Sonar Posted on December 02, 2021

#1 Walleye fishing  

Side scan saved the day. the weed, sand and mud edges were easily seen. The little sand dip in the weeds is where we found walleyes. They were on the sand right next to the weeds.

No wind, clear water and sunny. Only bass shallow so we looked deeper and found some at 22 foot.

Top arrow is mud

2nd arrow is sand

3rd arrow is weedlines

Bottom arrow is weed dip

weed dip side imaging

#2 Pay attention to sonar.

 

We were using spot lock to cast for walleye and Levi said look at the sonar. I quickly reeled up and dropped my jig and caught a 4 lb largemouth bass. The 2nd photo is the bass swimming away after I released it.

4 lb Largemouth bass with sonar

4 lb Largemouth bass with sonar

#3 Fish in bait show up well.

 

Notice the 2 bright yellow arches (green arrow) in the red bait (black)

fish in bait with sonar

#4 Sonar in vegetation usually sucks.

 

I looked at lots of areas and didn't see any fish and caught fish. But here is one example where the fish showed up.

fish in weeds with sonar

Fish in vegetation, you don't have to see fish to catch them. I often don't mark fish in weeds but still catch them like this one. I spotted the fish with my Aqua-Vu and dropped my bait near the camera!

no fish in weeds

fish in weeds Aqua-Vu

Green arrow shows nice fish on down imaging but looks small on 2D. It is probably on the edge of the 2D cone and the DI cone is wider so shows the fish better.

Reason to run DI and 2D sonar. I also use Navionics on my Lowrance and LakeMaster on my Humminbird. DI (down imaging) is better in weeds most of the time.

Down imaging fish in weeds

fish in weeds 2D

#5 Difference in cones from different transducers.

 

My Garmin PS30 shows the distance to the side the fish are.

Green arrow 3 feet to the left of the transducer which is mounted on boat's mid-line.

White arrow 8 feet to left.

2D sonar only tells you how far off the bottom and that the fish in the cone somewhere.

PS 30 fish

2D sonar fish

#6

 

Red circle fish

Black arrow weeds

Green arrow small boulders on hard bottom point.

Blue arrow bait balls that create shadows on side scan.

side scan fish and weeds

This should help get started in interpreting your sonar.

 

New video on weeds, panfish, sonar and my Aqua-VU Posted on October 29, 2020

YouTube Link

Find the fish, fish the fish and understand sonar with Aqua-Vu underwater camera Posted on November 14, 2019

Watch video

sonar and fish identification Posted on October 05, 2019

Using sonar, down imaging, Lowrance, Humminbird, and Aqua-Vu to study fish

 

watch video

Will the northern eat the sucker? Posted on October 10, 2018

Mostly fun and a little education.

Humminbird down imaging

watch video

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

How to find your fishing spots with your Aqua-Vu Posted on June 02, 2017

I use sonar to find fish every time I go out but sometimes the fish can hide. Two good examples are boulders and steep drop-offs. The sonar beam is reflected off the bottom on steep drops and off the boulders and the fish can’t be separated.

I drove over this drop-off that had boulders and didn’t see any fish with either the Humminbird or the Lowrance.

Humminbird Sonar

I stopped on the edge and used the Spot Lock feature of my Minn Kota trolling motor on the edge and dropped my Aqua-Vu camera down and found these crappies but not just here but each time I moved along the edge there were more crappie.

 

crappie

Watch crappie video here

Even the down imaging couldn’t separate the crappies from the boulders while I was sitting over them.

down imaging

Notice the crappies are very close to the boulders in the video.

 

They did bite and they posed for the camera before being released (I had fresh walleye back home).

crappie

 

Understanding the lake bottom with sonar and Aqua-Vu Posted on March 02, 2017

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

Understanding weeds, bait and fish with sonar and Aqua-Vu Posted on January 24, 2017

Watch the short video to get an understanding why weeds are important for fishing.

Watch Video

Humminbird down imaging

Lost Fish, How To Find Them With Sonar Posted on December 13, 2016

Ever wonder what to do when you are slowly moving jig or rig fishing and lose the fish on sonar?

I had these fish near weeds located with down sonar (2D and down imaging).

If they disappear I look at the side imaging on a different screen to see if they are left or right. Like this image.

I place the cursor on the fish on the side imaging and create a waypoint and then move the boat to the fish before they move too far. It is easy, once you catch a few fish this way you add it to your fishing tools.