Topic: Trouble with side imaging/598ci

[luxun54]

Having trouble getting the hang of side imaging on my new 598ci SI. When I record to SD card and look at  the images back on PC, I can see things clearly (see first attached image of a screen capture from a recording file today), so I think unit is OK. But I don't see anything like that on the screen in the boat. What I see on screen looks more like image 2 attached (from snapshot) -- lots of fuzzy white stuff, no definition to shapes, no structure being shown, even when I pass by and know there is a tree or branch or whatever in the water. For example, in image #2, those two thin lines at the top are two 5 foot diamater columns holding up a bridge that I passed under. I am guessing there may be something I should be doing with settings, but I have tried different things, still not coming together. Would welcome thoughts and suggestions.

[Humminbird_Greg]

If you are wanting those two 5 foot columns to show up wider (top to bottom) you would need to slow down the boat and/or speed up the Chart Speed.

It looks like you have some blockage on your Right Si sonar due to the repeating vertical lines that parallel the centerline.  Could that have been the boat motor down or something else?

[luxun54]

Boat speed was about 1 mph; I tried again the next day with boat at <1 mph and chart speed at 3, and columns were wider, but still seemingly not to scale??

Not sure where vertical lines came from? This is a trolling motor mounted transducer, but it should have been well below pontoons. Here is another screenshot from the next day?

[Humminbird_Greg]

Hmmm, I’m not sure why those lines would show up to begin with and now go away… Nothing was hanging off the trolling motor or the boat the first day that wasn’t the second day was it?

[luxun54]

There was no obstruction that I could see, but I did adjust the position of the transducer before the second trip, slid it back a bit as the front had been right up against the fin on the trolling motor. [On this motor, Minn Kota Traxxis, transducer has to be mounted behind the motor shaft rather than in front because of the fin under the propeller housing.]

Still not getting side images that tell me anything in the boat??

[4d-rock]

Just out of curiosity and for comparison.  Could you temporarily mount the transducer on the transom?  Just to eliminate the trolling motor altogether and see if things change.

[luxun54]

It's a pontoon boat, so there is no easy way to mount transducer on transom.  As it is, cable is kinda hardwired in place, with transducer on rear (supplemetary) trolling motor. It's definitely down below the pontoons, and all images were taken with trolling motor OFF (using front/bow motor only).

[Humminbird_Greg]

What are the Si Enhance menu settings that you are using?

[rnvinc]

I have found vertical pilings and bridge columns the most difficult structure to get a satisfactory SI image of...

I'm pretty sure it has to do with the fact that very few of the "sound pulse" pings are actually hitting the structure before I pass by it....

Like Greg said....:
*slow the boat down...to allow more pings to hit the piling
*speed the chart up...which will stretch the "successful" hit pings down the screen to "look like" a piling...

Rickie

[luxun54]

In response to Greg's question, these images were taken on default settings, though I have tried various other combinations.

Rickie, I am interested in your comment that you have had trouble with bridge pilings; I was thinking they should be one of the EASIEST things to image and see on a small screen since they are big and don't move? I was trying to see what I could learn from a clearly visible structure that might help me understand what I am seeing with murkier strictures, but it just confused me more.

[rnvinc]

We have to remember that the SI image being plotted onto the unit display is a compilation of horizontal "stacked" slices ...with each "ping's" data being only 2-3 pixels wide..(actually tall instead of wide)...

If the boat passes by the piling too fast...then (in my mind) only 2-3 sound pulse "pings" successfully hit the piling..

3 (successful pings) X 3 (pixels tall each ping) = 9 (total pixels tall on the SI image)...

That's not very many pixels to show a discernible piling...

Sometimes I think too much...lol

Rickie