I finally got a chance to take my Solix 12si out for a test run. I've encountered some issues I have questions about.
My setup: SI is set up using color 9, Sens=16, Cont=6, Clear Mode ON, Unsharpened. I'm running a restricted frequency range of 1,125-1,150 MHz in an attempt to extend SI, and avoid interference with DI. I settled on these settings to extend my returns out as far as possible.
This is as good a range as I was able to get:
There seems to be a possible silt layer from heavy rainfall in the last week, see the blue haze in the SI, and 'dust' in the DI:
2D shows the bottom about 1 foot shallower than DI. I put a depth offset in during setup, but I don't recall it being specific to 2D...
You can see that log's shadow in DI, too. Weird.
I'm running 2D as a 1D, 205-225 kHz, because I couldn't get massive clutter off the screen. I ended up running clear mode, surface clutter=10, sens=11, cont=20, and color=6.
DI is set up in Max mode, unsharpened, sens=14, cont=11, and color=11. I'm running a restricted high freq range of 1,250-1,300 MHz, to eek out max detail, and avoid interference with SI.
I found that running Playback a Recording to be invaluable for refining these settings.
Last edited by skid00skid00; 05-05-2017 at 02:38 PM.
Reason: more detail
Are your 2d and si transducers mounted at the same level? That's about the only thing I could see making a difference. I have my si on my jackplate and my 2d in my hull. That's almost 1' difference
I'm wondering if there was so much silt flushed into the lake, that it returned a strong enough signal for the unit to interpret it as 'bottom'. I saw some areas where it looked like two bottom signals, a foot or so apart. (Not the typical 2nd and 3rd bottom echo.)
I was getting what I think was excessive signal sent from the transducer. I had surface clutter set to minimize the return strength, had sensitivity set very low, and even broadcast just the high end of the 2D's high frequency spectrum, just to get the lowest return strength possible.
Yea I saw what your talking about. In a few images it looks like it may be showing all the silt and stuff as a second bottom. You've already turned everything down so I really don't know how to help you. That would have been my advice.
I don't think the geometry of the wider cone would show a raised bottom, when the bottom is almost ruler flat. I think that would show a wider 'red zone', since the hard bottom would still reflect a good signal even far away from the boat.
But your illustration is excellent for showing how that wide cone does some unexpected things. Thanks *once again* :) for your help. You're always there for me.
I started using a DI unit for ice fishing because the 2D cone @ 455 KHz is really tight and has better target separation due to the shorter physical wave length.
I discovered with an AquaVu that a wider beam will pick up stuff off to the sides and the center of the drawn line is usually the "true" bottom depth.
I always wondered in 40FOW why I could lower my ice jig "into the bottom signal" before it would actually stop.
I saw Chara weed down there, and realized stuff like that & loose siltation can show some strange stuff.
I learned ice fishing yellow perch in 60FOW that the bottom edge of the signal can show "bumpage" while perch sneak thru the cone belly tight to the bottom, and they are not showing "on top" of the bottom signal because they are further away at the edge of the cone than in the center of it.
You help others out with what you know, and for me that's all I could ever ask of you - and we're here to help each other get the most from out machines and to up our catch rates.
Robert
Newaygo CTY, MI
Helix12MSI G2N v1.84/Helix10MSI G2N v1.84/Helix10MDI G2N v1.84/ASGPSHSx2/iPilotLinkv2.15/2.04RC-1+2/
That's true bottom (at least as far as I know from sonar views over the last 6 months). I'm wondering if runoff (I wouldn't call it silt, I don't think you could actually feel it if you ran your hands through it, I think it's less thick than chocolate milk. At the landing, I could see bottom clearly in 4' of water) could be thick enough to return strong/red returns as shown.
This layer showed up as *dim blue* in the side imaging (and I didn't get a sharp edge transition from water to bottom), and you can see all the yellow speckles in the DI.
In these areas, when you pull up a dragged anchor, you get real heavy, sticky mud. It has to be scrapped off the anchor wings.
I don't think it's weeds. Not yet, and not that deep, either. Unless the zebra mussels cleared up the water much more than I remember from last fall! (Actually, visibility was only around 4').
It almost seems like stratification. But there's no chance of that on Lake Winnebago. Max depth 22', lot's of wind churn over it's 6 mile by 22 mile size...
My solix shows a fuzzy area about 2 feet from the bottom, then it is clear the rest of the water column. Pretty annoying since that is were the bass usually are positioned, so it is hard to see them on down imaging. If I turn the contrast up to around 13 it clears up some. Might try that. My sidescan also doesn't have a distinct difference between bottom and water column, making it hard to see bass on the bottom under boat like I used too.(this is on mega, 455 works much better for my needs)
I'm thinking that the Mega 'side lobes' are smaller/weaker than we are used to with lower frequencies, so there's not much bottom reflection. That might be a good thing as far as clarity is concerned.
Definitely makes you want to run DI to see what's going on under the boat, though!
Solix Mega SV issues, 2D / DI depth mismatch
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