In an earlier blog I wrote about needing Side image to get the most out of your Down Image scanning. In this blog I’ll show you an example when you needed Down Image to find the structure that is hard to see with the Side Imaging transducer. In this scan I am using my Humminbird Onix 10 Touch SI/DI unit. Then as usual I convert the recordings using ReefMaster Sonar Viewer software. In this blog I will only be posting three images and you can see why you still need both your Side Imaging and down Imaging transducer at the same time in most cases.
In most instances I use only my Side Imaging while scanning for structure and I use my Down Imaging to try and locate fish whether it’s bass, crappie, white bass or any other species of fish i might be after on that trip. When I’m scanning for structure with my Side Image I usually have my unit scanning out to 100 feet on each side. If I’m looking for fish with my Side Image and Down Image together I set the Side image range to either 50 or 60 feet. On my Side image I use the 455 kHz and on the Down Image I set it up to use the 800 kHz settings. This will usually give me the clearest images i have found on my units.
The color palette will be a matter of personal preference. On my Onix for example before all the software updates I liked to use the “Green” palette but with the last software update I find myself using the #2 “Amber” palette the most. On my 360 transducer in shallow water I like the “Gray” palette the best. As usual you will have the continually make changes on the fly with your “Sensitivity” and your “Contrast” setting during the scanning process.
Okay now for my first image from a recent scan I did on the water. I,n the image below you can see a lot of stuff in the water, there are lots of schools of bait-fish. You can see some larger fish near the bottom which could be catfish or Asian Carp. You can the edge on the old creek channel bank on the right side of the image. You can see some larger fish up in the water column under the bait-fish which could be bass, stripe or crappie. You can see what looks to be a tree limb on the lower left of the image and possibly a brush top almost in the center of the screen.
Now in the next image I am using the Down Image transducer to run the exact as area, as a matter of fact I was running both the Side Image and the Down Image at the same time to get this scan. But you can now see what I missed with just the Side Image transducer.
Wow, now what do you see in the Down Image scan? You can now clearly see the three big man-made brush tops someone dropped in the lake! You can still see the bait-fish and a few fish but not everything you saw in the Side Image scan image.
And finally in this last image I’l show you them side by side and see what you can and can’t see if you were only running one without the other.
Remember I was running both at the same time over the exact same area and I would have missed the three big brush tops without having them both on at the same time. So you can clearly see you need to run both at the same time to get the most out of your units. This is one reason you need the larger units like the 10″ or 12″ for the largest screen area you can see at once. I also run a Helix 12 SI Mega but most of the time I only use it for mapping as i find my Onix unit gives me the clearest image of the both of them.
I hope you get a little more understanding out of your expense tools you have added to you boat.