Humminbird Side Imaging Forums

General => General Discussion => Topic started by: sbeausol on January 09, 2019, 03:38:50 PM

Title: Side/structure scan in shallow water rivers
Post by: sbeausol on January 09, 2019, 03:38:50 PM
Hi - new member here.  I have some experience with sidescan and downscan.  I have a 23' center console with simrad NSS9 Evo2s, a B75M thru hull and structure scan 3D.  That is for saltwater fishing in coastal MA.  I also have a river boat (oar powered) I use to fish for trout etc on medium gradient rivers and I'm thinking of putting a small sonar system on it with a retractable transducer mount. This setup would be used more for mapping structure on the river bed instead of locating fish since I will have floated past any fish I would see on the sonar with no way of getting back to them. The water conditions I will be in would mostly be 2-3' of water and my hope would be to use sidescan to look for holes and structure off to the side of the boat maybe 50-100' in both directions. The river depth varies from 1-2' to >8' in some areas. Any idea if the side scan options out there are capable of working under these conditions?  I've tracked down many threads here and it seems users have experienced superior results with HB over other manufacturers in shallow water.  There is also a decent amount of software out there to process recorded sonar data that works with HB data.  I've toyed with the idea of using a deeper pro+ or fishhunter cast-able wifi transducer but my suspicion is that side scan would be superior for mapping river bottom structure in larger swaths at a time.  Anyone have any comments on my application, and if there is a certain HB that would be recommended over another? 
Thanks!
Title: Re: Side/structure scan in shallow water rivers
Post by: newkid4si on January 09, 2019, 10:13:45 AM
sbeausol

      One of the primary requirements for good SideImage images is that the boat moves in a straight line at a constant speed.  Under oar power and in a river, this may be an issue.
      That said, your images may not need to be perfect.  A depression or rock may display well enough so you'll know it's there. Someone with shallow water experience over that range
      may chime in. I don't have that experience.


         Good luck,
          Mike
Title: Re: Side/structure scan in shallow water rivers
Post by: sbeausol on January 10, 2019, 08:57:34 AM
Good points.  Constant speed is reasonably easy since the river current dictates that and although variable, is generally constant.  The straight line part is a bit more challenging since navigation consists of a decent amount of 'zig-zagging' to avoid obstacles.  I plan to mount the trasducer on a poll which can be deployed and retracted as needed.  I wonder if allowing that pole to rotate with the direction of the current might address that issue.

Any comments on performance in the shallow water conditions?  For example, if I'm sitting in 3' of water will I be able to detect a hole to the side of me that is say 6' deep?
Title: Re: Side/structure scan in shallow water rivers
Post by: rnvinc on January 10, 2019, 02:52:44 PM
Not my image  ...: (bream beds)  ...
(https://lh3.googleusercontent.com/XiVcCP0_AAyRx4phTAzNCVSvINKF50qeQoZIpnkUm5vSqF2IrqKYisbfTJWT5qIPBZ4-z90lDurHHblY093rJeZxFWwpetT2VAaEV34vmUNFxe5jsCnHSQYyanxWNHhCBlEVBGj0Wg=w400)

Not my image  ...: (creek channel 40ft to right)  ...
(https://lh3.googleusercontent.com/I-Pi7e80Vbfl0RmGZklmlW_HCmXZ8dsj65CqnLPXoE3h4Dc9tvblQEPsip6qEfuh_wok55VhYNnIRm54veCccv6l5U4YoPp3LzSKkKj6F6EJ6zsTFnUbsM0bVIoqwXqBd24o9_k41w=w400)

Rickie
Title: Re: Side/structure scan in shallow water rivers
Post by: newkid4si on January 10, 2019, 09:23:31 PM
Rickie posted two good images to help you decide.  In the first, the boat is in the middle and you are "looking" 50' to the left and 50' to the right. The depth at the top of the image is 1.8 foot. The depth at the white symbol in the center is 5.9'. The dark spots are bluegill beds about the size of your hand and an inch or two deep. If they had been rocks/boulders, they would be bright white.

In the second image, the depth is a consistent 1.6'  The dark area to the right of center is what a depression or hole would look like. Maybe not quite that pronounced as that is a channel, but enough that you would know it's there.


         Mike
Title: Re: Side/structure scan in shallow water rivers
Post by: sbeausol on January 10, 2019, 09:55:07 PM
Looks good. I don't think my simrad would perform that well in shallow water. Now I guess the question is what model makes sense. Any recommendations on good value? Probably the helix line?
Title: Re: Side/structure scan in shallow water rivers
Post by: newkid4si on January 10, 2019, 10:19:25 PM
I can't help you there as I am not knowledgeable on the current units. Someone will help you though. If you get to the point of choosing between two units, I recommend that you choose the larger screen size, especially for SideImage viewing. Go to a BassPro, Cabela's, etc, an play with a small and large screen unit in demo mode.

      Mike
Title: Re: Side/structure scan in shallow water rivers
Post by: rnvinc on January 11, 2019, 01:58:23 PM
HELIX units are the general choice for most users  ...

SOLIX units are touch and more customizable  ... but have a much more complicated Menu System  ...

Rickie
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