Most mid-range and just about all high-end fish finders at the moment are geared up with side-scanning sonar, high-quality down-scanning tech, and normal 2D downward-facing sonar.
Consequently, it’s virtually by no means a query of which one you need, however fairly which one is healthier at the moment and on this place.
And whereas loads of anglers perceive easy methods to use and fish that 2D sonar, few actually perceive how the extra technologically superior side- and down-imaging choices work or easy methods to benefit from them.
Humminbird’s Saltwater Area Employees Supervisor, Invoice Carson, says, “I see it each day… 90% of the anglers make the most of 10% of their fishfinder. One of the highly effective capabilities is Down Imaging and that is by far the least used of the sonar applied sciences.”
Are you one of many 90% not getting all of the efficiency you paid for? Or are you one of many savvy 10% that wring each greenback out of your fish finder?
Should you’re unsure in regards to the variations, benefits, and downsides of side-scanning versus down-scanning sonar, we’ll cowl every thing you must know.
So hold studying!
Desk of Contents (clickable)
What’s Down-Scanning?
Down-scanning sonar offers an exquisitely detailed view of what’s instantly beneath your hull.
To offer that element, down-scanning sonar makes use of very excessive frequencies, usually within the 455kHz to 1.2MHz vary, as they carry extra data. After all, the flip facet of this coin is that top frequencies can’t penetrate the water column in addition to decrease frequencies can.
Constitution captains and match execs use DI sonar greater than you do.
That’s a easy truth.
And the reason being clear – actually.
Anglers who actually perceive their fish finders will run normal 2D sonar when transferring, particularly in deep water or over muddy or sandy bottoms the place normal sonar can detect fish like they’re sporting a radar beacon. However when looking fish over rock piles and different construction and canopy, they’ll verify the 2D return with the down-scanning sonar, because it offers higher fish discovering functionality when fish are scattered amongst rocks or clustered very tightly collectively.
BJ Silvia, Flippin Out Charters’ Captain working out of Newport, Rhode Island is among the transformed.
“I’ll admit, at first I resisted Down Imaging,” he confesses. “I felt I might do all of it with 2D and Facet Imaging. That every one modified this spring. I occurred to activate DI in a rocky space and immediately started marking tog, one thing not finished with regular 2D sonar.”
“This summer time we received on faculties of striped bass which had been glued to the underside. I’m speaking lots of of fish packed collectively, 5-feet excessive. Different boats would get near see what I used to be fishing, take a look at their screens and drive away not realizing what they noticed. I do know they went over the varsity and mistook it for backside. In the event that they knew what my Humminbird SOLIX confirmed, it’d make them sick!”
Have in mind, the thought isn’t to run DI sonar always, at the least not till you’re on the fish.
As an alternative, you employ DI to verify what the 2D sonar is telling you, particularly when the underside is cluttered and there’s loads of construction and canopy.
DI will completely select fish that 2D sonar misses.
Simply ask Captain Dom Petrarca of Coastal Charters Sportfishing.
“For years we’ve seen the enormous clouds of bait on our fishfinders and assumed the tuna had been in there,” he says. “With conventional sonar the bait reveals up as a washed-out cloud, solely exhibiting gamefish after they’re separated from the pile. It was additionally tough to tell apart the kind of bait. Down Imaging modified all of this and is nice for chopping via the bait, revealing large tuna swimming within the center. I can clearly establish the kind of bait and know if the fish are on herring, mackerel or smaller sand eels so I can modify my presentation accordingly.”
And that’s the explanation to run DI whereas actively fishing: not solely are you able to select the predators from the bait with ease, you possibly can actively see what they’re consuming, adjusting your bait option to match.
That’s a bonus few anglers would knowingly move up.
Benefits
- Extraordinarily detailed photographs
- Spots fish that 2D sonar errors for the underside
- Identifies species of each bait and predator, permitting you to make knowledgeable selections
Disadvantages
- Not helpful whereas transferring shortly
- Restricted vary in comparison with 2D sonar
- Like 2D sonar, solely sees what’s instantly under the hull
What’s Facet-Scanning?
Facet-scanning sonar makes use of a number of transducers positioned to emit soundwaves on to the facet of your boat, usually with ranges as much as 200 ft to every facet.
And like down imaging, the element SI sonar offers is created by very excessive frequencies, often within the neighborhood of 455kHz to 1.2MHz.
The black stripe down the center of the picture is the world instantly beneath your hull. To either side, you get a view of the water column, choosing up backside particulars and fish with excessive element.
Facet-scanning sonar is an superior instrument, and for many anglers, it’s completely sport altering.
You’ll be able to run side-scanning sonar whereas transferring, recognizing fish you’d miss on normal 2D mode.
That makes it extremely efficient in open water or whereas trolling, and you’ll dwelling in on faculties you’d move and by no means see within the outdated days. Simply remember the fact that the quicker you’re transferring, the extra lag you’ll generate, which means that photographs you see might be seconds outdated, exhibiting what’s behind you.
It’s additionally an superior possibility in shallow water.
2D sonar’s low frequencies actually punch via the water column, however as you’ve little question already skilled, in shallow water, the sonar cone is simply too small to be actually helpful, and interference with the underside could cause the sonar to run amok.
As a shallow-water instrument, SI sonar is unbeatable, and in contrast to DI, many anglers take the time to essentially be taught the ins and outs of this tech as a result of its benefits are instantly apparent.
However hold a couple of issues in thoughts.
First, SI is totally blind to what’s beneath your hull. As soon as you discover the spot you’ve been searching for, you’ll wish to swap to 2D and DI to essentially get on the fish.
Second, it will possibly’t penetrate the water column in addition to 2D sonar, particularly CHIRP.
And third, the photographs will be complicated or simply plain exhausting to learn on small screens. To get essentially the most from side-imaging sonar, you really need the most important display screen you possibly can afford.
Benefits
- Extraordinarily detailed photographs
- Spots fish that 2D sonar would miss out to every facet
- Identifies species of each bait and predator, permitting you to make knowledgeable selections
- Nice for trying to find fish whereas transferring
Disadvantages
- Restricted depth when put next with 2D sonar
- Blind to what’s instantly beneath your hull
- Photos will be exhausting to learn on smaller screens
How the Professionals Use their Fish Finders
As you possibly can see, there’s a time and a spot for 2D, DI, and SI. Fish finders are positively not a “set it and neglect it” instrument!
In deep water, constitution captains and match execs will run 2D sonar searching for fish, usually together with GPS positions and predetermined sizzling spots like wrecks, humps, submerged islands, drop offs, weed beds, and so on. – the stuff all of us search for to seek out fish.
The extra cluttered the underside is, that’s, the extra variance it affords the sonar, the extra possible it’s that they’ll pause and swap to down imaging to search for fish that 2D sonar misses. That’s additionally true in the event that they discovered fish with the usual sonar: they’ll swap to DI to get extra element, spot extra huge fish, and get a very good learn on precisely what’s occurring down there.
Are tuna slamming mackerel or squid? Are the bass holding tight to a submerged tree, or are they scattered close by?
In shallower water, inshore or in lakes the place the water isn’t a lot deeper than 50 ft or so, they’ll run side-scanning sonar, sweeping possible spots and searching for fish that aren’t the place they predicted they may be.
If the water is effectively and really shallow, they could simply cease, lowering lag, and utilizing the SI to establish precisely the place to forged. In barely deeper water, they’ll swap to DI to get that killer element.
After all, mastering their fishfinders wasn’t an accident, and it definitely didn’t occur in a single day. They took the time to be taught to make use of the assorted options supplied, practiced studying the returns, and received to know which sonar possibility to make use of and the way they work collectively as a successful mixture.