Fishfinder picture interpretation

[MSBruno]

Took this pic and was wondering if fellow OFC'ers can help interpreting this image.

 

This was over an area approximately 50ft in diamter.

 

Thanks in advance.

[johnnyb]

I remember reading a tutorial on setting your fishfinder settings by Gord Pyzer, and he was talking about cranking your sensitivity way up, and that when you go a bit too high, you'll get a double image. It looks like the contour of the bottom is mirrored perfectly by the contour of the "cloud" in the middle of the screen. If that happens again, I'd notch the sensitivity down a bit and see if it disappears.

OR....take Terry with you and have him drop his underwater film studio down there to see what's really happening

 

 

[kickingfrog]

I know there are a lot of people who know more about interpretation than me (and more about your brand as well) but my first thought was thermocline, but without knowing the lake or time of year I'm just spitballin'.

 

Looking forward to what others have to say.

Edited August 31, 2010 by kickingfrog

[Spiel]

One or the other explanations from Johnnyb and Kickingfrog are likely correct.

 

Knowing where you were and what settings the sonar was set at would aid me in deciding which of the above posts is correct, but I'd bet it's one of them.

[MSBruno]

sensitivity is all the way up.

 

Location on lake is deepest part of the channel leading out to the river (Trent Severn)

[Spiel]

sensitivity is all the way up.

 

Location on lake is deepest part of the channel leading out to the river (Trent Severn)

 

 

 

Given that I would suspect Johnnyb has the right answer.

 

Another possibility though could be receiving the sonar signal of a nearby boat.

 

[mercman]

looks like a thermocline or turbulance caused by an underwater current. both of these can help you find fish.

 

 

[canadadude]

Looks like a double bottom to me,almost every unit I've used will get this from time to time.Turn you sensitivity down.

[jediangler]

My first thought is, you need to wipe your screen clean of all those water spots.

 

I learned to read mine by drifting over small stones, sand, weeds, and solid rock in shallow water where I could see bottom. Then I watched how each was interpreted on the screen so I could recognize it later in deeper water, where polarized glasses just couldn't cut it .

[Fisherpete]

My fishfinder looked similar to that a bunch of times on Simcoe this winter... it was schools of herring, sometimes only 5' down in 100' of water!

[Guest ThisPlaceSucks]

i've had similar phenomenons with my unit when trolling parallel along the very edge of a dropoff.

Edited September 1, 2010 by Dr. Salvelinus

[danc]

I have no idea what it's saying. I use mine for water temps only. Having said that, why do I have a $500.00 thermometer in my boat?

[MSBruno]

Thanks everyone. I'll turn down the sensitivity and report back.

[SylvanOwner]

In regards to the double return, I thought (and have experienced) the second return showing at double the distance below the surface (not half or so as this appears to be), you have to manually zoom out to a scale that displays at least double the depth in order to see this....... .....and you can only accomplish this over relatively hard bottoms. Really hard bottoms and powerful, narrow beamed transducers should be able to show a third return (according to the articles I've read) although I've never been able to produce this.

 

My guess is that it's the thermocline......and yeah, clean your screen

 

Dan

 

p.s. there's a joke in there somewhere.....Terry

[MSBruno]

Same spot with 50% sesitivity

[spincast]

I view it as an indication my lines should be about 10 -15 ft down if I want to catch a fish?

But then I have also found that frequently my rod will get hit when my screen has been blank for a bit, and they dont do squat when the screen is loaded? I have yet to find the MADE BY MURPHY sign on the darn thing, but I know its there.

Show me the bottom and the structure and leave hooking the fish to me.............

one charter guy I now uses his to show his lines behind the boat, and darn if he don't know how to land fish? so LLoyd - how did you set that up?

[jedimaster]

a big giant musky with some perch swimming on top of it.

[Fisherman]

Like others said, possibly a double return, but then again it's a humminbuzzard. I would find some clear water with a hard bottom and give it a try, turn off the fish ID too. Fish finders don't know the difference between lobster poop and a fish, they mark a lot of bunk and show it as a fish. Friend of mine proved that with his cannonball..lead fish