Thread: Explain this

the jig is in the water column its movement is going to show a left to right movement because that's what SI see's, a left or right of center of the boat axis reading

or am I wrong, that's my take anyway

The SI is showing up and down movement of the jig. The black area on the left and right of center-line both display the area directly below the Xducer. That black area is the depth of the water below the Xducer thus the jig will show the up/down movement.

The jig is on the left side of the Xducer according to the screen setting displayed.

That is how I understand it after a Lowrance seminar.

Originally Posted by Cane Pole

SI/DI of jig in shallow water. You can easily see the jig up and down movement in DI. So why is SI showing side to side movement (changing distance from centerline)? No, current, no breeze.

Actually it is moving closer and farther from the td as it's jigged up and down. I don't interpret the image that way though, if you rotated the image 90* the jig would appear to be going up and down, which it is. I view ss images like humminbirdgreg (I think) described in a video. If you printed the image and folded it in the center, where the td is, then folded each side out where the bottom meets the water column _||_. This what the df is seeing.

Because the jig IS "changing distance" .... and as you've previously noted, the transducer/sonar ping can only tell distance between it and the object that's reflecting the signal. The interpretation of that signal (the image) isn't shown in actual 3d ... but in 2d on the screen ... so the reflected signal is displayed "sideways". The DI is directly down +/- ... so the reflected signal is displayed "up/down".

That's how I understand it, anyway.

... cp

Originally Posted by CrappiePappy

Because the jig IS "changing distance" .... and as you've previously noted, the transducer/sonar ping can only tell distance between it and the object that's reflecting the signal. The interpretation of that signal (the image) isn't shown in actual 3d ... but in 2d on the screen ... so the reflected signal is displayed "sideways". The DI is directly down +/- ... so the reflected signal is displayed "up/down".

That's how I understand it, anyway.

... cp

Right answer. Distance to transducer.

Canepole,i don't see nothing strange about that pic,as he jig bait up and down the bait gets closer then far from ducer