Bow Mount sonar unit- SI, DI, 2d, or something else?

In your opinion, what is the best set-up for the bow mounted sonar unit?
Side Imagining unit, Down Imaging unit, no frills 2d sonar unit, or something else?
Assume your captains chair has your main sonar unit that you use for most everything and the bow unit will be strictly for when you are moving via the trolling motor. What functions does it need to perform and why?

I see it all the time, what do I put up front? I have the same question and have been asking myself this question for over a year now. I can make an argument for any of the options. I realize trolling motor will play a part, assume you have the perfect trolling motor to match your bow mounted sonar unit perfectly.

Why side-scan on the bow?? you can use it as 2D DI or side scan, so you have more options as to what to look at. The 'ducer in on a "DA-DUCER" device and works well that way.

I think it's all relative to your type of fishing. I'm kinda unique in that I run a stick steer and have my big unit mounted by my right knee. And bow unit right in front of me. I can run big unit on chart or chart and SI while running bow unit on 2d or DI. Most important to me is GPS on both. That way I can mark stuff on bow and transfer to main unit or vice averse. I mainly spider rig so that suits my purpose. If I had the opportunity I would run SI also.

WITH SI ON BACK,I WOULD WANT 2D,GPS AND TRUE DI ON FRONT,NOT CRAZY OVER COMPUTE TYPE DI FROM SI ,SOMETIMES YOU GET A GOOD PIC BUT MANY TIMES JUST A LAPSE OF BOTH SIDES,HUMMINBIRDS BIGGEST MISTAKES IMO,NOT BASHING JUST STATING A FACT,HAVE 1199 AND 859 DI AND LOVE THEM,ALSO HAVE LOWRANCE ELITE DI

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Originally Posted by genec

WITH SI ON BACK,I WOULD WANT 2D,GPS AND TRUE DI ON FRONT,NOT CRAZY OVER COMPUTE TYPE DI FROM SI ,SOMETIMES YOU GET A GOOD PIC BUT MANY TIMES JUST A LAPSE OF BOTH SIDES,HUMMINBIRDS BIGGEST MISTAKES IMO,NOT BASHING JUST STATING A FACT,HAVE 1199 AND 859 DI AND LOVE THEM,ALSO HAVE LOWRANCE ELITE DI

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I agree somewhat. Humminbird would have been better off, displaying the right and left peizo's in separate views(not blended). If using a humminbird si unit for di, it's best to keep the boat off to one side of the structure/fish. By blending the two sides, they actually degraded the si images,that appear in the DI view. (imo) a humminbird 2d unit, coupled with 360, is the only setup necessary for bow.Di,is fun to play with tho. With Lowrance, there spot light scan, doesn't really work. So I wouldn't recommend Lowrance. Garmin has a forward scanning, but if the transducer is mounted on the trolling motor, it's very limited. You would be better to mount it on a du, ducer apparatus of some kind. Still seems to me, it's limited....

Thanks for the reply's so far. Based on the comments, seems like dedicated DI or 2D is preferred up front. You can always pull SI off the rear transducer. Forward imaging would be nice, 360 is not cheap.

A Helix 9 2d/360 is $1640. No sales tax and free shipping at Universalmania.com

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Originally Posted by kosmo

A Helix 9 2d/360 is $1640. No sales tax and free shipping at Universalmania.com

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I could not find that combination Kos, they showed both items individually but separately they were about $1900

Just looked again. It's $14077.27.. http://i826.photobucket.com/albums/z...ps6nfshvu9.png http://i826.photobucket.com/albums/z...psreuut2dl.png http://i826.photobucket.com/albums/z...psbz9k8kva.png

I've ordered several items from universalmania.com....

When I tried to look up the 360 all I got was the transom mounted unit and it was $1300, thanks

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Originally Posted by vic n

When I tried to look up the 360 all I got was the transom mounted unit and it was $1300, thanks

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That's a good price for the transom 360 also. If I were going to buy another 360,it would be the transom mount. I happy with the way mine works.

I voted for DI on the bow. I don't care who you are, you get a few fish stacked up on the bottom and you get a blob. With DI you get some separation and can really see relative sizes. Plus you can see a little to the sides so if you are working up into a cove or something you don't drive past fish that were just to the edges of your 2d.

I cant wait to get my new bow unit hooked up, found a screaming deal on a 859 di head unit on ebay. Gonna swap out my 597. Should be sweet.

Those with DI, are you using MinnKota's Universal Sonar? What kind of image do you get with the US?

I'd go with a DI unit and 360.....You have everything you might want.

Also.....You can't use the US2 for a DI unit .... it is 2D only.

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Originally Posted by BobB

I'd go with a DI unit and 360.....You have everything you might want.

Also.....You can't use the US2 for a DI unit .... it is 2D only.

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Do you mean SI and 360? I didn't think the 360 worked with DI? :dono

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Originally Posted by Hanr3

Do you mean SI and 360? I didn't think the 360 worked with DI? :dono

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The 360 will work with a 2D/GPS, DI, or SI Helix unit.

From the 360, you can get DI and SI in addition to the 360.....The SI and DI will not be a sharp as a HDSI transducer would be, but give some pretty good SI imaging.

I recommended a DI unit because it is sometimes nice when crappie fishing to get higher quality DI than you could get with the 360 alone.

If you paired a Helix DI unit and 360 at the bow with a SI unit at the console utilizing the HDSI transducer on the transom....You would have a setup that would be great for crappie fishing.......If you consider the Ethernet sharing capabilities, you could view the 360 and share the other transducer data .....You'd have everything available from either location. (You could also do this with a Helix at the bow and a 99 series unit at the console.)

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Originally Posted by Hanr3

Do you mean SI and 360? I didn't think the 360 worked with DI? :dono

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I think that you might be thinking that 360 is only a transducer that rotates. 360, is completely self contained. It sends the signal to the piezo's. receives and converts. It only lacks a display for viewing via Ethernet. (that's why I was recommending, it paired with only a 2d sonar) you would have all views covered. You will sacrifice some si and di quality, but the overall advantage of having the 360 would be worth it (imo).

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Originally Posted by Hanr3

Do you mean SI and 360? I didn't think the 360 worked with DI? :dono

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If you pair a Helix si unit or a Helix di unit, with a 360. Those views will not be available while the 360 is running in the rotating mold. Only the Onix, will allow si/di/ and 360 simultaneously.

When I asked this question locally the answer I got was "2D" on the bow (I got a Lowrance 520 up front). The reason being that DI and SI show a slice which is then painted on the screen as you move. 2D shows a cone which will show much more when sitting still (as in over a brush pile). The other alternative is a DF/FF that will show both a 2D and a DI side by side like my Helix (on my console) which lets you interpolate (put together) the images to get more detail than either one alone will show.

Now that I installed GoFree WIFI, I can look at anything sonar related anywhere on my Iphone. Handy tool. 2D,DI. SI, whatever is selected on the unit. I might get an Ipad, then I can control any Head unit anywhere in the boat via WiFi.

No wires!!!!!!!!!!!!!!!!Lovely.

I'm running SI at the transom (999)
DI at the bow (859) along with TM 360.

I like the 360 but do not use it to it's full capabilities because of the screen size on the 859 BUT that is soon to change!!
Plan on mounting another screen (H 12 maybe) just for the 360 and use the 859 for a chart screen or 2d.

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Originally Posted by BobB

...
If you paired a Helix DI unit and 360 at the bow with a SI unit at the console utilizing the HDSI transducer on the transom....You would have a setup that would be great for crappie fishing.......If you consider the Ethernet sharing capabilities, you could view the 360 and share the other transducer data .....You'd have everything available from either location. (You could also do this with a Helix at the bow and a 99 series unit at the console.)

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My current thinking is a DI unit on the bow (Helix9 DI), SI unit at the council with HDSI, mount a 360 on the transom and ethernet it to both the SI and DI units. Then I have 360 from the bow and council. SI at the council, and DI at the bow. Currently I have a 899HD SI at the council and it supports the 360.

The problem I see with mounting the 360 on the bow is the trolling motor must be in the water to use. With the 360 on the transom I can use it anytime, except high speed.

I like your thinking though. Thanks for planting the seed.

Consider the Helix 10 DI unit instead of the 9 .... It has a higher pixel density and the imaging will be better.

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Originally Posted by BobB

Consider the Helix 10 DI unit instead of the 9 .... It has a higher pixel density and the imaging will be better.

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Does it really have a higher pixel density, or does it just have more pixels because it has a bigger screen?

The Helix 9 has about 3000 more pixels / square inch than the 9.

The Helix 9 is 800 X 480 and the 10 is 1024 x 600.

I wish i plunked down the extra coin for the helix 10 instead of the 9. A little extra resolution and a touch more screen would go a long ways. More the resolution than anything else.

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Originally Posted by BobB

The Helix 9 has about 3000 more pixels / square inch than the 9.

The Helix 9 is 800 X 480 and the 10 is 1024 x 600.

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The Helix 10 has a 1" bigger screen then the Helix 9. I expect it to have more pixels, it has a bigger screen. The question is, are there more pixels per line of image on the Helix 10 compared to the Helix 9? I did the math. Results below.

Helix 9 = 103.66 ppi
Helix 10 = 117.51 ppi
That certainly isn't 3000 more pixels per square inch. More like 13.85 more pixels per square inch, or roughly 13%.

Is the Helix 10 DI worth $300 more than the Helix 9 DI?

How to do the math.
https://en.wikipedia.org/wiki/Pixel_density
Calculation of monitor PPI

Here is the way I calculated it ....

Helix 10:
8.75" horizontal x 4.9375" vertical = 43.203 square inches.
1024 pixels x 600 pixels = 614,400 total pixels.
614,400 pixels divided by 43.203 Sq inches = 14,221 pixels per sq inch for the Helix 10.

Helix 9 :
7.75" Horizontal x 4.25" vertical = 32.9375 Sq. inches.
800 pixels x 480 pixels = 384,000 total pixels.....So the Helix 10 would have 230,400 more pixels than the Helix 9.
384,000 total pixels divided by 32.9375 Sq. inches = 11,685 pixels per sq inch for the Helix 9.

So, 14,221 - 11,685 = 2,536 pixels per sq inch difference between the Helix 9 and the Helix 10.

I rounded the 2,536 up to 3000 as a rough number......I have no idea what that ppi designation means.

With a combination of the larger square inches and the higher pixel density, the Helix 10 screen clarity will be a lot better than the Helix 9. This theory has been verified by people who have used both.

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Originally Posted by BobB

Here is the way I calculated it ....
I have no idea what that ppi designation means.

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ppi= Pixels Per Inch
A simpler calculator.
Pixel density calculator - King's Calculator

Helix 9 = 103.66 ppi
Helix 10 = 117.51 ppi
Helix 12 = 124.75 ppi

For contrast, my
A 50" Plasma 720p tv has 25ppi.
A 50" LED 1080p TV has 44ppi.

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Originally Posted by Hanr3

ppi= Pixels Per Inch
A simpler calculator.
Pixel density calculator - King's Calculator

Helix 9 = 103.66 ppi
Helix 10 = 117.51 ppi
Helix 12 = 124.75 ppi

For contrast, my
A 50" Plasma 720p tv has 25ppi.
A 50" LED 1080p TV has 44ppi.

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Since the Helix 10 has 614,400 total pixels..... It's hard to accept those numbers as an actual pixels per square inch.....which was what I calculated..

I was just trying to answer your question of whether the Helix 10 has a higher pixel density than the 9 ..... Starting to wonder why I bothered.

You guys are using 2 different calculations to get to a moniker "terminology" called ppi that doesn't even mean the same depending on which calculation you're using ...

This is from the wiki ...
http://i477.photobucket.com/albums/r...psplo6qeyp.png

This calculation to get the moniker "terminology" ppi (used in monitor measurements) is not the same as the calculation to get "total pixels in a 1 square of screen space" that Bob is calculating - but both using the same moniker terminology of "ppi" ...

Both calculations are correct - but the term used as "ppi" in each calculation does not mean the same thing ...

Regardless of which calculation used - or which term used to express the pixel density in a monitor/screen = the HELIX 10 should give better images than the HELIX 9 ...because each calculation sums higher with HELIX 10 ...

Rickie

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Originally Posted by BobB

Since the Helix 10 has 614,400 total pixels.....

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I appreciate you answering, forced me to do the research and the math.

I did the same exercise with my 899C HD SI unit. 133 ppi. Interesting, the 899 has more ppi than the Helix 9. However everyone claims the Helix units have better image quality, and based on my Presleys store visits I would agree. I am still digging, both unit are using TFT (thin film transistor) LED screens, see below for technical explanation.

Thin Film Transistor Displays
http://techin.oureverydaylife.com/tf...lay-37558.html
TFTs are a type of active matrix display that controls individual pixel updates several times per second on the screen to update the image relative to the content source. These displays are built from a thin layer of transistors located on the back of the screen that handles screen animation. The display receives information from a computer or video source and updates the screen contents row-by-row so many times per second that it looks like the entire screen is updating content in real-time as opposed to being a collection of frames. A more advanced type of TFT technology called In-Plane-Switching improves the screen viewing angles.

This ties in with Rickies comments. Should give a better image because it has more pixels, regardless of the math used. How/why does the Helix 9 have a better screen image than the 899 when the Helix unit has less ppi and both units are using TFT screens?

The brighter 1500 nit screen of the HELIX makes the images "perceive" as better ...

We can't compare apples to apples of HELIX vs previous core units because the "nit" is different ...and the way the human eye perceives this "brighter screen" factor ...
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Simply raising the brightness level on your smart phone makes the images on the phone screen "look" better ...

Rickie

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Originally Posted by rnvinc

The brighter 1500 nit screen of the HELIX makes the images "perceive" as better ...

We can't compare apples to apples of HELIX vs previous core units because the "nit" is different ...and the way the human eye perceives this "brighter screen" factor ...
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Simply raising the brightness level on your smart phone makes the images on the phone screen "look" better ...

Rickie

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What is NIT? - Never mind, I goggled it.
No idea about smart phones. I don't have one and never plan on getting one.
If the only difference is a brighter screen why bother? I can see my 899 screen just fine in all light conditions. I was hoping the video processing was better or some other technical aspect was enhanced to give a better image.

I have had an 897 2d, 597 di, 859 di, and helix 9 and the 2d is much easier to read and more clear on my helix. I dont know what to attribute this to as far as hardware but the returns are much more distinct and with less clutter. And not just from a larger screen the same goes for watching 2d in the triple view. Sometimes i wonder if the transom di ducer i have on my trolling motor is worn out but i really cant say.

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Originally Posted by OrangeAgent

I have had an 897 2d, 597 di, 859 di, and helix 9 and the 2d is much easier to read and more clear on my helix. I dont know what to attribute this to as far as hardware but the returns are much more distinct and with less clutter. And not just from a larger screen the same goes for watching 2d in the triple view. Sometimes i wonder if the transom di ducer i have on my trolling motor is worn out but i really cant say.

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The 2d sonar beams on di units are 200/455 khz with 20/16 degree cones. A regular 2d sonar is 83/200 khz and 60/20 degree cones so you see much more of the bottom. DI in the bow only shows what is now under the boat...if you want to see what's coming and what's under a spider rig right now then regular sonar will be better. The cone on DI units using 2d sonar is likely less than 3 feet at 10 ft of depth while on a 2d unit it would be 10 feet.

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Originally Posted by JohnK9027

The 2d sonar beams on di units are 200/455 khz with 20/16 degree cones. A regular 2d sonar is 83/200 khz and 60/20 degree cones so you see much more of the bottom. DI in the bow only shows what is now under the boat...if you want to see what's coming and what's under a spider rig right now then regular sonar will be better. The cone on DI units using 2d sonar is likely less than 3 feet at 10 ft of depth while on a 2d unit it would be 10 feet.

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How does that compare to a 360?

I have read the entire thread again, great info.


Sent from my iPhone using Crappie.com Fishing mobile app

With your snow removal money, get a 360!


Sent from my iPhone using Tapatalk

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Originally Posted by Hanr3

How does that compare to a 360?

I have read the entire thread again, great info.

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360 will show farther from the boat ... And orientation from the boat ...

2d will show "something within the cone coverage somewhere" ...

Rickie