Here's an interesting shot ...
What is causing the anomoly in the right SI water column ...??
(credit to Spearfish III for the image)
Attachment 274206
Rickie
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Here's an interesting shot ...
What is causing the anomoly in the right SI water column ...??
(credit to Spearfish III for the image)
Attachment 274206
Rickie
This boat has a da'ducer stick up too close to the TM and is picking that up? Weird that the shadow is still while the interference/return raises and lowers.
It's a really long fish!!
I've seen a trolling motor do something similar or something that passed thru already and you are seeing the "wake like disturbed water".
LOOKS LIKE A COUPLE CABLES,BUT I DON'T KNOW
That's a good one Vic ... But no ... It's not da'ducer apparatus® ...Quote:
Originally Posted by vic n
And the shadow you are referring is not a shadow ...(because there's a matching dark line in the left also) ... We will deal with this dark like separately ...
Come on guys ... Some good guesses so far ...
Rickie
How about a drift sock? I think that's what they call them!
Drift sock wouldn't be that deep. Someone forgot to pull in the anchor.
I have to think it's something connected to the boat.....down rigger? But that wouldn't be moving as much as this. Planer board to the side with a bad crankbait under it, or an umbrella rig?
I TOO WANDER ABOUT DOWN RIGGER AND LOOKS LIKE BOAT TURN ALITTLE AND STRAIGHTEN BACK UP
lochness monster?
Water skier. :biggrin
Is it bigger than a bread box?
I don't have a clue.....Something going up and down in depth and casting a major shadow on both sides.....Weird that when it appears to go deeper.....the shadow is steady.
:popcorn
The fisherman is pulling a down rod with a bait attached. The two bright marks are the sinker the second is the bait.
I don't think the shadow has anything to do with it. That looks like traveling up a feeder which is showing up on each side as the boat is in the middle.Quote:
Originally Posted by BobB
THE OBJECT IS ONLY ABOUT 4 FEET AND IS LET DOWN TO ABOUT 8 FEET OR STILL 4 FEET AND HE TURN BOAT TO LOOK LIKE 8 FEET DEEP, AND IF DOWM RIGGER HE WAS NOT FISHING THEN, TOO SHALLOW AND TOO NEAR BOAT,SO HE MUST HAVE SET IT JUST TO WHAT IT ON SI?
A ladder hanging off of transom?
I'm not sure what's showing in the picture that rickie, has posted, but it's looks similar to what's in this picture, that I do no what's Making the white line on the right side.the main difference here is water depth. If the water was deeper in my picture and I got closer, then it would appear in the water column only...http://i826.photobucket.com/albums/z...pshtxebbdj.jpgQuote:
Originally Posted by rnvinc
Kosmo.....It looks like some kind of pipeline in that shot of yours....?:dono
I don't think the boat is turning any, the image is to clear, not skewed at all. Whatever it is could be moving horizontally (closer then farther from the boat) instead of vertically in the water column. It would show as being deeper on the screen, distance not depth.Quote:
Originally Posted by genec
You'd have to be traveling perfectly up the middle of a feeder for the shadow to show like that.....Kosmo's shot has a little bit if that effect also....I think we have a double quiz.Quote:
Originally Posted by larryb227
Ok guys ... Some great discussion ...
Many different ideas being offered ... And additional "mini discussions" of each of those ideas being analyzed ...
These "mini discussions" (within the main topic) is how we learn tidbits of info that we didn't even know we were learning ...
Here is the quote from Spearfish III ...:
Attachment 274210Quote:
Originally Posted by spearfish III
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Now someone explain why the echo return from this drift sock is "undulating"...(you guys have already touched on the answer in the "mini discussions"...
UN•DU•LATE (verb) ... move with a smooth wavelike motion
Rickie
And the dark lines are not shadows ...
We will discuss this next ...
Rickie
Dang.....drift sock was my first thought......:biggrin
Are the dark lines the "tunnel" effect caused by the all in 1 transducers? I have never seen a shot where it was that pronounced, if that is it.
I have never seen that effect on my SI units, but there is some of it on Kosmo's shot also.
Because the sock is moving left to right? Ie steering corrections?
Ok, I didn't expect it to be a drift sock.but the two pictures are still similar. The object is just under the surface in both pictures, leaving no shadow to reference but they are different in that one picture the object is moving with the boat , while in the other that's not the case.
Kosmo, is that a floating swim line rope?
I think that as Spearfish III is trolling, he is making course corrections, which causes the wind sock to drift in and out
It's an empty river barge.its down in the water about 1 ft.thats why there's no shadow in the shot.my transducer is mounted on my trolling motor and I'm moving it slightly as I'm going by the barge and that's why it's not showing a straight line.Quote:
Originally Posted by justinp61
Ahhhh..........I see said the blind man.Quote:
Originally Posted by kosmo
IF I UNDERSTAND U RIGHT RICKIE, I THINK THE ROPE TO DRIFT SOCK IS STAYING IN SI BEAM ALL TIME
If I am figuring it correctly isn't it 30" in diameter? Maybe that is something else to address, how big is the actual object appearing on the snapshot?
Quote:
Originally Posted by vic n
As we don't really know how Spearfish III trolls for trout ... We can't be sure if the sock is moving away from the xducer (maybe sinking with no float)... or the xducer is moving away from the sock (as the boat turns)...Quote:
Originally Posted by Redge
We can be sure that the distance between the xducer and the sock is changing ...
Rickie
Okay....now let's talk about the shadow. I was over on BBC and saw virtually the same shadow on another SI shot
I don't have a clue on the shadow! Looking forward to learning something new.
"Dark lines" aka "Ghost Lines" aka "Washboard lines" anomalies show up in side scanning images most commonly in examples of side scan images captured while using an xducer that has both "side pointing" SI piezoes and a "down pointing" DI piezo ...
LSS 1
Attachment 274211
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LSS 2 (not as prominent but still there) ...
Attachment 274212
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Onix
Attachment 274214
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Garmin
Attachment 274213
Overlapping slice beams can create an effect similar to this beam form example which end up showing in the SI image as the dark lines ...
Attachment 274215
Rickie
Thanks Rickie!!
There is another SI anomaly that shows up sometimes as a matching left and right SI dark line called the "null sector" of the beam form ... But it's usually less prominent and not necessarily in an xducer with both "side pointing" SI piezoes and a "down pointing" DI piezo ...
Attachment 274216
Rickie
That's what I thought...:biggrin