Sonar quiz #6

[rnvinc]

Below are 2 screenshots....

One is considerably darker than the other...(referring the SI only)...

List the reasons that can create these differences in SI images...(and explain each reason separately)...





Rickie

[wilbur]

Not sure what your asking Rickie, looks like 2 different pallet colors to me.

[justinp61]

On image 2.
1- you could be on top of a ridge with deeper water on both sides.

2- it's a Lowrance

3- the black line on the left almost directly under the boat is something I haven't seen. Maybe the way the td is mounted.

4- I'm on my phone and the images are small.

[kosmo]

One is 455 the other is 800. Ill wait on the other response that your looking for so others can ponder for little bit

[Nory]

I'll give it a shot.

1. boat on traveling over a ridge with deeper water off to the sides.
2. hard bottom under the boat, transitioning to softer on the sides.
3. difference between 455 and 800 khz. One of them is darker on the edges? Not sure which one though.

Keep the quizzes coming Ricky! They are fun and a real help!!

[brettw]

Could be a tilted mounting job

[skigill]

Thats a humminbird shot. sounds like reasons are covered pretty good.

[rnvinc]

One is 455 the other is 800. Ill wait on the other response that your looking for so others can ponder for little bit

All of the scenarios the guys have listed are indeed possibilities...and most are self- explainitory ...

Now someone explain the technical reason kosmo's answer (and Nory's) ...is a possiblity...

Why is one frequency generally darker at the edges than the other...??

Rickie

[GroutScout]

Because it's not broadcasting as far and the signal gets weak.

[rnvinc]

Because it's not broadcasting as far and the signal gets weak.

And there we have it...just like lower frequency 2d "cone shaped" sonar pulses broadcast deeper than higher frequency 2d "cone shaped" sonar pulses..

The same theory is true for SI "thin slice" pulses...lower frequencies broadcast farther...

Rickie