Post your interesting sonar images

[Larry3215]

Im starting to think Im the only sonar nerd on the forum! Its kind of embarrassing

[BentRod]

Im starting to think Im the only sonar nerd on the forum! Its kind of embarrassing

Nope! I love following the sonar readout and trying to figure out what is being returned. I only have black and white traditional sonar, so interpretation is a fun challenge.

I enjoy looking at the images you post up. Keep it up!

[DavidA]

Keep 'em coming! I too only have a basic fish finder but will definitely try to relocate the 'cabin' you found on the bottom of Spencer Lake! Very interesting!

[Larry3215]

Whew! Im glad Im not alone in my nerdiness! ;) I Love messing with this stuff - especially when I cant be on the water actualy fishing. Sometimes the things I learn even help me catch a fish or two I might not have other wise.

These are some shot from Killarney Lake near Coeur d'Alene, Idaho. We were after pike (not much luck there) but we had gotten a tip that there might be crappie in one part of the lake. So after NOT catching any pike all morning, we decided to go look for crappie. Now I know why they were hanging out in that area. There must be several thousand board feet of timber in the water in that section of the lake!

I think its interesting to see how the same structure looks when you are using different types of sonar. In some of these you can see the same structure on traditional, downview and sidwview.

As we drifted across the lake this is what I was seeing on traditional 2d sonar.

Then I looked at the downview screen.

Then I started watching the sideview.

[Larry3215]

More sideview shots

[The Quadfather]

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[The Quadfather]

Don't feel all alone here. I enjoy this thread. I just have not put a memory card in my unit, so haven't posted.

[DavidA]

Having neither downview nor sideview, if you can add any interpretation of what is shown, it would be greatly appreciated. Thanks.

[cobrar543]

I had a blue line like a heart beat. UNDER the bottom. First time I have ever seen that. Didn't have my phone or I would have taken a shot of it

[Larry3215]

I had a blue line like a heart beat. UNDER the bottom. First time I have ever seen that. Didn't have my phone or I would have taken a shot of it

Was it anything like the picture in the lower left quadrant? That can be caused by a very hard or very smooth bottom return or a double return if you are shallow. It would help to see an actual screen shot to be sure though. Check your owners manual. There is usually an easy way to capture what ever is on the screen and copy it to a memory card if your unit has a slot for a card.

[Larry3215]

Having neither downview nor sideview, if you can add any interpretation of what is shown, it would be greatly appreciated. Thanks.

This might help. I have circled the same piece of structure that shows up in all three views in the above post. It looks to me like two logs or branches are laying across each other to form a V. It could also be part of a tree that has a large branch forming the V. There were a lot of broken and downed trees all around the hill sides near that part of the lake. I dont know what caused it but something tore through there and dumped a lot of timber into the lake at some point in the past.

You can learn different things from each view.

First is the Downview shot. Downview uses a narrower more focused beam to scan the bottom. That means it will show the best detail of the structure - like logs, rocks, or anything hard. Its close to taking a picture of whats passing directly under the transducer. Downview is great for looking at structure on the bottom right under the boat. Not so good for seeing fish unless they are in a school. Schools show up pretty well as balls.

Unfortunately, that narrower beam and the way the screen is drawn, means that soft targets, like fish and weeds, dont show up all that well when compared to traditional 2D sonar images. Fish are also drawn much closer to scale as far as thier size on the screen. So you may see a nice large arch on 2D sonar but the same fish will only be a small spot on downview and even smaller dot on sideview. You can see a lot of small dots scattered around the branches and near the bottom. Some of those are small fish - crappies and very small perch. Many if them are just noise on the screen. Its pretty much impossible to tell the difference between noise and fish when they are just tiny dots. Thats where it comes in handy being able to switch to traditional 2D to look for the fish.

If you look closely at the traditional 2D shot below, you will see fewer targets around the two branches but some of them look much bigger. The traditional sonar is designed to make fish returns show up better and they do. There is also a stack of arches under the right hand log. Those are almost certainly fish. They arent very big, but I think they are fish. Just to the right of the circle on the bottom is a blob of red sticking up. In the downview shot above it looks to have layers. Thats probably some sort of plant matter or small branches piled up on the bottom. The traditional sonar cant see as much detail so it just looks like a blob but the downview can see more of the actual structure.

That smudge to the left of the circle might be a small bait ball of very tiny perch - or it could just be the top of a weed of some sort.

The sideview images have the same features and limitations as downview in that they use a very narrow beam to scan the bottom - but it scans out to both sides instead of straight down. Sidescan also has the advantage AND the disadvantage of covering a much wider area of the bottom. Thats an advantage because you can see whats on the bottom over a much wider area out to both sides of the boat. Several hundred feet each way with the right transducer and good conditions. Its realy good for covering a lot of water looking for structure that might be holding fish.

But - thats a disadvantage as far as actually seeing the fish because they look even smaller when you are looking at a large area. Remember they are drawn close to scale size. They will often only be a tiny dot on the screen or not show up at all unless its a good sized bait ball or they are close to the boat.

[Larry3215]

I edited the above post to add more details. I can go into more on the sideview images - or anything else - if anyone is interested in that. Sideview can be the most difficult to interpret. Mostly because what you see on the screen isnt really what it appears to be.

[DavidA]

Larry: That was a lot of effort and is definitely appreciated. I spent a bit of time going back and forth between your words and the images and then comparing the images to each other. Fascinating! Question: Do the side scanning and down view images form the same way as a traditional 2D image i.e. constant refreshing on the right and the image moves to the left, with the 'oldest' being furthest left? Again, thank you for taking the time.

[Larry3215]

Yes, except that sideview typically comes down from the top to bottom - newest at the top. The screen for all views - except Garmins new Panoptix - is constantly scrolling even when the boat is sitting still.

Panoptix is a whole new ball game and is nothing like any previous sonar for recreational users.

[Larry3215]

I just noticed I had the CHIRP turned OFF and the transducer set to a single frequency in the traditional sonar views above. I just did a software update and forgot to check the default settings. More of those small dots in the Downview pics would probably have shown up as larger arches if I had CHIRP turned on.

[Larry3215]

Here are few shots from our unsuccessful halibut trip to Port Angeles over Memorial weekend. We marked good numbers of bait balls and fish that I think were salmon. If they get things open for salmon I think there will be at least a few to catch.

This shot has some more bait balls in deeper water along with a few fish that might be salmon and a couple of very large returns that I think might have been halibut. These were the largest returns Ive seen that deep, so they were good sized fish what ever they were.

This shot was interesting partly for the bait balls but mostly for the illusion created on the screen when you go from very shallow water, then accellerate out to deeper water then slow down and turn back into shallow water. Makes it look like you crossed a deep canyon with very steep sides when in fact it was a fairly steady drop off from shore..

[cobrar543]

Came across this on Mayfield last weenend. Nothing for ages then this.

[Larry3215]

Interesting shape. What ever that was it had fish hanging around it.

[Toni]

Or a tree stump decorated with dodgers

[Larry3215]

Yup!