Topic: What's this #1: fish?

[sonarbear]

Hi,

I was wondering whether any of you know or have a suspicion what the objects in the pictures are (w/ and w/o autogain adjust). They are located in the Elbe river, a 200 m major river of Germany. I was drifting down in the middle of the river at 2 knots. The river holds some catfish and quite a few Zanders, a type of European walleye. The bottom is sand with dunes, depth is 2.5 m currently.
What do you think, fish or stones? How can I distinguish them?

[Bob B]

It looks like mostly dunes washed by the current with rocks mixed in.

I'm not an expert on river SI, but I am looking mostly at the shadows and deviation in the return intensity.  I do see a few brighter white steaks mixed in that look like fish.

[rnvinc]

I'm thinkin stones also ...

Rickie

[fishreed]

Rocks and stones.....to me.

[sonarbear]

Thanks for the opinions! How would fish look like?

[newkid4si]

You wouldn't by any chance have been making a recording while you were doing this ?   If so, Humviewer will have your answer.


             Mike

[rnvinc]

Thanks for the opinions! How would fish look like?

Fish close to the bottom ...


And fish look reaaaaly small the wider the SI Range ...


Rickie

[mike fish]

Wow that's a lot of fish rnvinc.  Nice detail.

[sonarbear]

In the first image the fish don't exactly match the shadows and are detached. So I guess that would be a difference? But in the second image, I don't really see the difference to my posted shots. Could you maybe explain? Thanks!

[Bob B]

In the first image, the fish are a little higher in the water column since the fish shadow is a little further from the fish.

In the 2nd image, the fish are closer to the bottom since the shadow is very close to the fish.

[newkid4si]

Rickie

    In your first image ( DI-sonar-SI) did you have the SI sharpness at 'High' to make the fish standout ?

            Mike

[rnvinc]

Rickie

    In your first image ( DI-sonar-SI) did you have the SI sharpness at 'High' to make the fish standout ?

            Mike

OMG Mike ... I'm not sure ... That was a screenshot from my 1197 maiden voyage way back in 2010 ...

I do know that spot is a very soft bottom and fish normally stand out very well against it ...

I'm guessing Sharpness was Off and SI sensitivity was cranked up as high as I could get it without washing out the image ...

Rickie

[newkid4si]

LOL !!!  The reason I ask was that I was reading one of your post... from 2010... about putting the sharpness at 'high' to make the fish stand out.

          Mike