Using SideScan in deep water

[ohkw]

Hi all!
I am fishing at a lake in Austria, which has bathtub like characteristics. From the shore, it gets deep very quickly, being around 200ft+ deep at most of the area of the lake. The water features a very distinct thermocline in 30 - 40 ft ater depth during summer months. Big fish tend to feed pelagicly in deep water areas.
I was wondering if there is a way to use sideVü / sideScan in deep water for pelagic sharpshooting in a way so that it shows only the upper 50ft of the water column. Showing the whole water column would be completely useless, because there are only low oxigen concentrations below the thermocline and rarely any fish deeper than 70ft. I am currently using an EchoMapUltra 102sv with GT54UHD transducer plus LVS12. Do you think it possible to configure it in such a way, that it interpretes the thermocline as lake bottom while also showing the fish above of it in a meaningful way?
Thank you in advanve for your opinon.
Cheers!
Stefan

[Fishysam]

Well with lvs32, you can manually set depth range on forwar at 30 or 40 ' deep and run range out to 120', turn the unit to one side and stare at it as a grain of rice will only briefly be on screen. Maybe use trails to help you notice them. As far as SI I have no clue. No settings to do that. But if you could write software it's possible

[BigBry]

PS30 would be your best friend.

[ohkw]

But if you could write software it's possible

Is there something like an API for Garmin fishfinders? This task would be relatively simple if the software modules were open source. It would be sufficient, to use the regular down-scan display for this. Instead of having the "folded" sidescan representation, there would be just two downscan representations, one left one right. The user could limit the representation to some distance, while having in mind that those "down-scans" are oriented somewaht diagonally down left and right of the transducer.
Maybe Garmin could pick up this idea theirselves.

@Bigbry
PS30 would do perfectly but is still quite expensive. I'll have an open eye for a rebate event or maybe I could find it second hand somewhere. On the other hand, there isn't much space for a third transducer on my vessel.

[LWINCHESTER2]

I'm not sure I understand what you are asking for. So feel free to ignore this post. First, there's no API or open source options.

Since the range setting is obvious, apparently that's not what you are referring to. It sounds to me like you want to split the ping return into two parts; isolating and keeping the part coming from the side while disregarding or ignoring the part coming from the bottom. That's not possible so I don't understand how it would be relatively simple to produce the software even if you had the access and tools to do it. Each ping, while narrow front to back, is exceptionally wide from top to bottom, reaching from the surface to bottom and under the boat a a bit beyond that. It puts centerstage that one of the biggest advantages and disadvantage of side imaging is that all you know from a return is how far it is from the transducer. There's no way to determine where in the water column (depth) the return is coming from. It could be just under the surface or that same distance under the boat, or to the side at any angle. Bigbry nailed it.

[ohkw]

@LWINCHESTER2
As far as my understanding goes, classical 2d sonar, as well as 2d down scan do not necessarily need a bottom to work properly. When fishing in free water, I can set the depth to 40ft and I am only seeing fish signal, thermocline and nothing else. (When fishing over real deep water, the unit won't even find the bottom and is unable to display the depth, but displaying the e.g. upper 40ft still works, seemingly. I hope this is correct thus far.
From all what I got in terms of explanations how sidescan works, the "hardware" is basically two downscan transducer, but rather than being oriented straight downwards, those are oriented sideways diagonally down, left and right to the boat.
If regular downscan works properly without bottom, so should do the sideways diagonal version of it.
In other words, if I would tilt my GT54 UHD transducer 45° sideways, and display regular down scan for 40ft range, this would display me the upper sin(45°) * 40ft = 28.2ft of the water column at one side of the boat.
Does this somehow make sense or is there a fatal mistake in my thinking?

[BigBry]

@LWINCHESTER2
As far as my understanding goes, classical 2d sonar, as well as 2d down scan do not necessarily need a bottom to work properly. When fishing in free water, I can set the depth to 40ft and I am only seeing fish signal, thermocline and nothing else. (When fishing over real deep water, the unit won't even find the bottom and is unable to display the depth, but displaying the e.g. upper 40ft still works, seemingly. I hope this is correct thus far.
From all what I got in terms of explanations how sidescan works, the "hardware" is basically two downscan transducer, but rather than being oriented straight downwards, those are oriented sideways diagonally down, left and right to the boat.
If regular downscan works properly without bottom, so should do the sideways diagonal version of it.
In other words, if I would tilt my GT54 UHD transducer 45° sideways, and display regular down scan for 40ft range, this would display me the upper sin(45°) * 40ft = 28.2ft of the water column at one side of the boat.
Does this somehow make sense or is there a fatal mistake in my thinking?

Perfect Sense. You seem to be describing the old Hummingbird Matrix. The limitations with Sidescan for the OP would be the narrower cone at shallower depths. I’ve always experienced diminished returns towards the surface with sidescan. The adjustable angle on the PS30 is useful as you can go high and wide with your coverage if need be. The PS30 returns are not diminished whatsoever higher in the water column for some reason. I know what the OP is looking for and I’d start saving my money for a PS30. If only I’d had a PS30 15 yrs ago when I used to chase big summer time holdover trout hugging the thermocline.........

[ohkw]

I agree that the PS30 is currently the best solution for this task from Garmin. It appears to me that this transducer can be directly connected to the Echomap Ultra units via the ethernet port, and does not need an additional "blackbox" or ethernet hub, am I right?
I am wondering if there might be already a successor for this transducer on the way, as it its already more than 5 years since it's release with the panoptix lineup. Its price didn't go down much since ... but looking at the videos already got me an appetite for buying one ^^. I'll wait until the season starts in May, and ask my sonar dealer if there's something in the bushes regarding a successor. In the meantime I'll keep an open eye for a special offer or sale.
Thank you very much for your advice!
Cheers!
Stefan

[LWINCHESTER2]

@LWINCHESTER2
As far as my understanding goes, classical 2d sonar, as well as 2d down scan do not necessarily need a bottom to work properly.

I disagree. Most 2d sonar I've seen has to first establish depth of water so it can set ping speed. I expect down imagining to be no different. It's just a different element with a very different cone.

From all what I got in terms of explanations how sidescan works, the "hardware" is basically two downscan transducer, but rather than being oriented straight downwards, those are oriented sideways diagonally down, left and right to the boat.

The two side elements are usually identical, but down element ordinarily has a much tighter left-right cone angle.

Most providers don't disclose much of their technical information. Humminbird has been more open in that regard. They have stressed that side imaging will not work without a good determination of the depth. Last I read, this source of the depth is the 2d element.

[dricha21]

What does pelagicly mean?

[ohkw]

What does pelagicly mean?

Sorry, should have been "pelagically".

I am not sure if the term "pelagic sharpshooting" is also used outside of europe. It comes from sweden, and specificly targets large specimen of Zander and Pike in the pelagic zone of lakes (Pelagic zone - Wikipedia). Its mostly about locating fish in free water zones of lakes with the sonar, where the difficult part is navigating your boat exactly above a fish signal.
I am not entirely sure the term pelagic fishing is used in eglish speaking areas. I'm from Austria, so my mothers tongue is German.


.

[Fishysam]

I have no clue if you can write code for garmin or not. Ocean fish are palagic as well as muskies. The bass that chase herring are lund and only come to the bank to spawn are palagic.

[BigBry]

I agree that the PS30 is currently the best solution for this task from Garmin. It appears to me that this transducer can be directly connected to the Echomap Ultra units via the ethernet port, and does not need an additional "blackbox" or ethernet hub, am I right?
I am wondering if there might be already a successor for this transducer on the way, as it its already more than 5 years since it's release with the panoptix lineup. Its price didn't go down much since ... but looking at the videos already got me an appetite for buying one ^^. I'll wait until the season starts in May, and ask my sonar dealer if there's something in the bushes regarding a successor. In the meantime I'll keep an open eye for a special offer or sale.
Thank you very much for your advice!
Cheers!
Stefan

Not much to improve on the PS30 so not sure about a successor. It’s a niche transducer and just a very useful tool in the tool box. If one wants better detail, there’s down/side view. Want to see an even better view, count scales and fins or see how the fish orient to structure or react to your bait, there’s Livescope. If one wants a quick real time view of the entire water column and bottom as they’re searching, map with QD or watch their lure behind the downrigger ball, there’s nothing better than the PS30 period. Find something on the PS30 and then you dig those other 2 tools out to check it out. Wait and see if they release a successor. If they do, awesome. The original PS30 will be discounted and be well worth purchasing at a discount.

[SamMule]

IMO, PS30 or PS22 would be your best choices. Returns are large and very easy to see regardless of depth/distance.
I think you will find that fish returns are very small and more difficult to see on LVS12. Trails can help, but I feel like they have a tendency to make the screen very "noisy" if you're moving at all.
SideVu can work for finding fish suspended in the water column, but is nowhere near as accurate at Panoptix.
If you're "Sniping" fish in any scenario, you need to know exactly where they are. Nothing else on the market comes close to Panoptix in that aspect.

FWIW, I fish deep. Very deep, and out of all of the thousands of dollars of garmin gear I have, the PS30 has become the most effective tool to ACCURATELY locate fish in relation to the boat.

[ohkw]

Is the 3d historical function somewhat useful in navigating to fish signals that you've already passed? What I found was, that what makes pelagic fishing difficult is that when you move your boat very slowly, you won't find any fish. But when moving faster, you moved already over it before you can get your lure down. The forward view of LVS12 makes this a little easier, because you can see the signal coming and maybe manage to stop the boat in time. Although the very small area covered by the LVS12 down rarely gets the fish "into spotlight".

[SamMule]

None of the 3d views seem to be very good for finding fish. For me anyway...

IMO, if you want to "spotlight" fish, the PS22 will work much better for you than LVS12.
The beam covers so much more water. Fish will be easier to see on it as well.

[LWINCHESTER2]

22The problem with the PS21/22/30/31 is that it can be difficult to separate a school of bait from a school of catchable fish, especially if the school of catchable fish school tightly like crappie and white bass. Spotted bass and walleye are easier to discriminate since they don't school as tight. Depending on the situation the distinction can be made based on the depth of the return.

[ohkw]

This shouldn't be a problem as the catchable fish, like large free-water pikes and zanders, do not tend to swim around in schools. I guess those big fish should appear differently on the display. What I do not like though, is that the power and signal cables are separate cables. I prefer avoiding to much cable mess. I am using a "borika-fasten" system to mount and unmount my transducers at the rear of the boat. Can't let them mounted while the bot is in the marina, or they might get damaged or stolen. Therefore, the cables ar not wired within the hull. I also have no idea yet, where to put that third transducer ;)
Anyway, you guys have been a big help. Thank you all very much!
Cheers!
Stefan