Fish Finder Training – Screenshots & Interpretations

[Ketchup]

I read the first few pages of this thread last year. Just read every page and what great explaination in several different shots.  Next weekend, weather permitting, and after install of Garmin, I will post some pictures for you to check out. I took a few yesterday around the Cape area with DI and sonar to show wife the difference. Excited to get this new unit going. Thanks for the thread and for the answers to my coming questions. 

[J-Doc]

Quite welcome. 

Has not been any screenshot activity for quite some time. I'm always ready.

[J.E.]

Interesting. I just found your thread.

[Ketchup]

Ok J, here ya go....

Fished Long Creek area today. Caught 8 LM and 2 Spots. Still trying to better understand the relation from what im seeing on my graph, and what the fish on there are doing and what lure they may want. 

On these 3 shots, it looks to me like feeding fish. I motored over this shot, took a picture of the screen for you, then turned around and threw a crank bait over that area, catching a 14" LM on the first cast. 

question is, how to tell feeding fish from inactive fish just doing a drive over?.  Do the arches always mean active fish?. Wish i would have took one of the DI of that area. 

[J-Doc]

Lots to discuss here. I need access to a computer to mark up the images.  I'll try that tomorrow.

 

First thing to do is some homework.  I know, this isn't a class...lol! No quizzes either! ;-) 

You need to understand how basic sonar works.  Ever see Zona use the Cone of Injustice? How he used the big orange cone to look down underwater?  Sonar is like that.  It sends a signal in the shape of a cone. The signal is returned (much like your eyes function) so the image is reflected like an arc because of how a fish is shaped and the signals always weaker on the ends of the object it detects, thus the slope or tapering of the arc. 

 

Now...

Think cone shape and viewing or registering signals.  If it (fish) is on the edge of the cone or the view angle of the cone, the signal is weaker and will not show up as strong.  If it's on the very edge, it may show extremely weak.  The deeper you are, the larger the diameter of the cone.  In 20ft dropshotting, your cone is only a couple feet in diameter.  Thus why it's harder to dropshot in the wind when the boat is moving frequently.  (If you're using the graph for dropshotting). 

Streaks are signals reflected by active feeding fish.  They swim up to take a peak at your transducer often.  Then swim back down.   You get long lines or long arches when that happens.  Fish was curious. 

 

You can also see streaks busting through bait balls.  Those are definitely actively feeding fish. Fish the outside edge of the bait, never in it.  They get target locked on that particular bait.  Don't match the hatch, make it a bit different.  Try bigger or smaller baits of different variation in color.  Matching never works for me on bait balls. 

[Ketchup]

Thanks as always. Great explanations.  I look forward to the mark up of my pictures to see what is actually what. I'm determined to learn this part of being a better angler. I can beat the shore with the best of them, but that deep water stuff leaves me puzzled more than not. 

[J-Doc]

Ketchup.

Here is my comments on the screenshots.  Hope this helps.  These comments are based on what I have learned by watching Dr. Sonar DVD's (HIGHLY recommend btw) and my own experience using sonar.  Before getting my HDS Gen2 graphs, had I known more about what I was looking at I could have easily used a $100 graph and benefited from it greatly vs. just using to read "depth" and occasionally seeing fish arches on it. 

Because I have learned to read "arches", I NEVER use "fish symbols".  Fish symbols are just a different view or way to communicate a signal.  Think of it like a text "font".  You can change the look of the word by changing "fonts" but it's still the same word or letters. 

In the markups, I commented on what I saw.  There were few "active" fish present in the images but that does not mean you were not finding active fish. If you find a bait ball as shown in these images, you can bet there will be predatory fish nearby eating at will randomly. 

[J-Doc]

Go back to bottom of page 13 to see how cone angles work as a refresher if needed.

THIS IS KEY.  Once you understand how the cone angle works.....it will all "click" and you will get it.

Here is the link to the Zona show I referenced where he used a viewing cone to watch/spot the fish.

Zona's Cone of Injustice

[Ketchup]

Man, thanks again J. Great review of what those shots show. As I studied these pictures again this morning, guessing what I saw, my thoughts were pretty on par with what you stated. The arches making up tree branches never clicked until you stated that. The upper water column never came to mind either. I just figured prop wash every time.  

 

Those larger archers "possible catfish" was a guess for myself. I figured either a roid sized walleye, or a shark had invaded TR.  again, thanks for the mockup. I will have more for ya as I see things I'm unaware of.  

[J-Doc]

Quite welcome. Keep them coming. This thread stays too quiet. 

I was going to say those catfish marks looked like striper marks but I knew someone would say there are no stripers in Table Rock.  (Haha)  Seriously though, they do look like striper marks.  I do believe in this case theyou are catfish.