Humminbird Side Imaging Forums

General => General Discussion => Topic started by: sonarbear on May 12, 2016, 04:55:00 AM

Title: What's this #1: fish?
Post by: sonarbear on May 12, 2016, 04:55:00 AM: 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? [attachimg=1][attachimg=2]
Title: Re: What's this #1: fish?
Post by: Bob B on May 12, 2016, 05:19:33 PM: 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.
Title: Re: What's this #1: fish?
Post by: rnvinc on May 13, 2016, 12:48:07 AM: I'm thinkin stones also ...

Rickie
Title: Re: What's this #1: fish?
Post by: fishreed on May 14, 2016, 11:44:48 PM: Rocks and stones.....to me.
Title: Re: What's this #1: fish?
Post by: sonarbear on May 15, 2016, 10:47:53 AM: Thanks for the opinions! How would fish look like?
Title: Re: What's this #1: fish?
Post by: newkid4si on May 15, 2016, 01:00:18 PM: You wouldn't by any chance have been making a recording while you were doing this ? If so, Humviewer will have your answer.

Mike
Title: Re: What's this #1: fish?
Post by: rnvinc on May 16, 2016, 12:56:49 AM: Quote from: sonarbear on May 15, 2016, 10:47:53 AM
Thanks for the opinions! How would fish look like?

Fish close to the bottom ...
(http://i477.photobucket.com/albums/rr134/rnvinc/HB/501cee8d-4382-4be6-b5ac-d71c728fe51b_zpsb1af3f86.jpg) (http://s477.photobucket.com/user/rnvinc/media/HB/501cee8d-4382-4be6-b5ac-d71c728fe51b_zpsb1af3f86.jpg.html)

And fish look reaaaaly small the wider the SI Range ...
(http://i477.photobucket.com/albums/rr134/rnvinc/HB/70FEFA12-98AC-4BAE-8A1D-18457A0BDD12_zpsbmplpfdd.png) (http://s477.photobucket.com/user/rnvinc/media/HB/70FEFA12-98AC-4BAE-8A1D-18457A0BDD12_zpsbmplpfdd.png.html)

Rickie
Title: Re: What's this #1: fish?
Post by: mike fish on May 16, 2016, 01:29:56 AM: Wow that's a lot of fish rnvinc. Nice detail.
Title: Re: What's this #1: fish?
Post by: sonarbear on May 16, 2016, 04:11:27 PM: 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!
Title: Re: What's this #1: fish?
Post by: Bob B on May 16, 2016, 04:21:47 PM: 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.
Title: Re: What's this #1: fish?
Post by: newkid4si on May 17, 2016, 12:43:45 PM: Rickie

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

Mike
Title: Re: What's this #1: fish?
Post by: rnvinc on May 17, 2016, 10:55:52 PM: Quote from: newkid4si on May 17, 2016, 12:43:45 PM
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
Title: Re: What's this #1: fish?
Post by: newkid4si on May 17, 2016, 11:50:06 PM: 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