Lowrance demos StructureScan, with “DownScan”
Lowrance demonstrated its new StructureScan system in Orlando yesterday, with a surprise added feature. As expected, a high-frequency, very-narrow-beam transducer collects bottom info on each side of the boat and builds an almost photographic, though somewhat distorted, image as you move along. In the picture above (click for big version), we’ve chosen to display only the curious structure on the left side of our track. In other words, in that left window our boat is at the top right corner and the window shows the water column and bottom extending out about 70 feet to our left and about 200 behind us. The lower right window is normal Broadband Sonar image, derived from a separate transducer, but that upper right window is something different, as is the structure being imaged…
The transducer that comes with the Lowrance LSS-1 has an unusual third element that pings a 60 by 5 degree scan directly down, and is shown on screen (upper right) as what Lowrance is calling DownScan. The view is like regular sonar, but with higher resolution applied to a much narrower slice of bottom. The sketch below tries to explain the DownScan and side scan architecture within StructureScan, and also illustrates the maximum depths claimed. We were in much shallower waters on Disney World’s major lake down here, which was unfortunately dull in terms of fish and structure. But I did see DownScan confirm what looked to be a fish hugging bottom on sonar, and I saw it lend more detail, or at least another point of view, to stuff we saw in the side scan. Like the large sunken wave machine seen above, which I’m told was only run once (I’d like to know more about that story!).
At any rate, it looks like Lowrance has developed another very interesting option the HDS series, like Broadband Radar easily installed and rich in near range detail. The fishing folk are already excited, and I’m thinking it may also work well for mooring tenders, salvage operators, and gunk holers. More to come.
What’s the power consumption of the transducer?
Looks cool. Now *please* tell me why Lowrance and Humminbird aren’t tilting their transducers forward and giving us high performance obstacle-avoidance sonar at a reasonable price?
Good question, Adam. If Lowrance wants to completely change the game and go after the sailboat market at the same time that’s about all they’d have to do. Ray and Furuno will have a hard time catching up to Simrad’s lead here, and yet I’d be willing to bet only Garmin will be fleet-footed enough to grasp the implications.
Modestly priced forward looking sonar/bottom contour display, integrated into existing (best) or new (okay) chartplotter/radar displays?
Is anyone listening? Lot of cruising sailors ready to jump on this bandwagon.
I suspect this “Side Sonar” is based on principals close to radar called SAR – Synthetic Aperture Radar. A SAR radar cannot look forward – only to the side. It needs to have doppler across the beam to resolve the angle location of each return. So it uses the motion of the platform that carries it to generate that doppler. The doppler resolution – created over time results in angular resolution that is comparable to an antenna with very large dimensions – a “synthetic aperture”.
So Ben – does this rig work when the boat is standing still or does the side structure detail disappear when you stop?
The only way to have forward looking sonar is to have a version that uses either a large scanned transducer (electronically scanned) or use it in a combined “real beam” and doppler beam sharpening mode. The resolution dead aheard and a few degees to either side of “zero” is poor but every where else out to 90 degrees potentially – the beam is sharpened.
I don’t have any idea if these radar modes are directly applicable – but it makes sense that something similar is possible. Any info on that Ben? I suspect that forward looking SONAR is not a small matter to make work Vs the side looking version.
Interphase and FarSounder provide the required unique forward looking sensors that are required.
DaveV, I don’t think Dopler is involved. StructureScan, like regular sonar, does work when you’re standing still, though the history image gets very dull because you’re looking at the same bottom over and over again. Even with three different sonar views, it’s hard to interpret what’s going on just looking at one screen shot, instead of seeing the image materialize as the boat moves.
For instance, I could guesstimate that the top left image represents about 200 feet vertically because I was on the boat. If we had been going faster, it would show more area with less resolution. I could also understand that the sunken wave maker is actually quite linear, and only looks curved because the boat turned during the time represented in the image. (A chart with boat track window would also help clarify the curve.)
Understanding the time factor will disappoint those who think you can just turn these ultra narrow beam transducers 90 degrees to look forward. Unfortunately, you just can not build an area image that way.
Anyone still baffled about how this works might appreciate the video here:
Very impressive. I would like to see images from an interesting seabed (well, off the coast of Florida might be as boring as the lake), and also to know more about what speed the boat was running that gave such a good image. I’m a sailor, so I guess speed shouldn’t be all that important to me, but…
The physics of the transducer must be very interesting. That’s where much of the magic happens, I would guess.
On a related topic, have they offered the user a discrete “kill switch”…a Transducer On-Off switch, readily accessable? At times I would like to be able to deactivate my depth sounder (presently a Raymarine) without affecting the other electronics, when in the proximity of wildlife – Orca, sea lions, etc. Whales in the Pacific Northwest must feel like they live in the midst of a Caribbean steel drum band.
You can select menu…fishfinder setup…DSM Settings…Ping Enable. Changeing that value to “disabled” will turn off your DSM’s transmitter.
Ben, I wasn’t really thinking about turning the transducer 90° vertically; I understand that wouldn’t work (unless you added some sort of side-to-side sweep motor and totally revamped the software).
I’m simply wondering what would happen if you angled the transducer forward (say 15° below horizontal), so that it builds up an image of the bottom ahead of you (of course the slant angle would be greater than the actual depth).
The State of Virginia was at one time considering hiring out-of-work watermen to clear the estimated 10,000 abandoned or lost crab traps from the Chesapeake Bay. They are still trapping crabs and have a significant impact on breeding. Saner minds prevailed, but the problem remains. I wonder if this sounder, or even the Humminbird has the resolution to pick up these marine-growth covered chicken-wire boxes in 5 to 25 feet of muddy water?
I think they may, Sandy, and I’m hoping to try out Humminbird sidescan later this summer and Lowrance version when it ships (November, supposedly). My waters are different, but can get muddy after a big rain event. By the way, StructureScan can record all the sonar, GPS, and sidescan data, which you can replay and create waypoints on. I’m not sure about Humminbird in this regard.
This is kinda neat…a promo video Bonnier made during the StructureScan demo. I’m generally nervous in front of a camera, but pulled this off in one take:
Gee Ben,I was wondering how you got all these neat toys to play with,I didn’t know you were a Yatching mag editor til I looked at the Lowrance video..ahah!
The structurescan looks really cool but I am waiting to see how it does in saltwater at depths.
Re Lowrance..a local boat dealer here on the Island has decided to drop Lowrance in favour of Garmin.
said they were getting too many Lowrance products returned.Not the first time I have heard this.
Any idea how either the lowrance or th humminbird works in saltwater? I have read several product reviews saying the humminbird unit didnt work at all over 20 or 25 feet depth in saltwater. Perhaps the sidescan to work in saltwater/waves will have to be a towed array.
Doug, I just saw some screen shots of StructureScan passing over a big wreck in 85 feet of saltwater. They’re a little wavy because the seas were running 2-4, but they still show a lot more detail than a conventional fishfinder image.
“humminbird didnt work at all over 20 or 25 feet depth in saltwater”
Norwegian diver obtain an image over 65m with an Humminbird SideImaging.
Screeshot here :
Normally it works until 30/35m in the french saltwaters.
(metric systeme rulez) 😉
Downscan announced @Humminbird by software update…
Im a tourney bass angler from Arizona. I have fished the local tourneys and some pro the past 4 years. Im ready to step up and fish the FLW SW next year. Here is my question. When I pull up to the dock I see these guys with those huge display color downscan fishfinders. That is a huge investment for me just trying to get started. Is it worth my while to upgrade now? I feel if I dont I may be at a severe disadvantage. Thanks.