Great explanation.I dont understand why they dont have a processor that can transform the image into a more friendly user format for us challenged guys.Maybe that is next ??

It's called Side Image, not down image.

Mark, I think you misunderstood what I meant. I didn't mean it showed 17.5 feet of bottom under the boat, (this gets hard to describe) I mean if the water is 17.5 feet deep then the blue area on the screen, on one side, represents 17.5' of the screen.The light area will be the remainder of the distance you set. If the water is 30' deep and you set the side distance at 30' there will be no light area shown at all. just the vertical water column of 30'.

Trust me guys, after a couple of trips you will not even notice the format. It actually makes sense and is a better way to view it. The screen and boat move in the same direction and the area behind the boat is actually behind the boat not scrolling to the side.

Thats funny Mark you are correct..My point is regardless of what its called it would be nice to have an image that was more user friendly when it appeared on the screen.I am more than sure I am not the only one with the same feelings on this technology and the way its displayed.As for Ernest's comments on getting used to the image I am sure that once you get a little experience that it gets easier as you go.

If you are not confused enough yet.... this is what I think I see

Great job Ernest! Thanks for painting the picture.

Ernest,

I was just trying to correct UJC (Jimmy's) interpretaion.

Didn't want him to think its the total Blue Area (17.5') out both side as he had stated it (49 = 17.5' + 31.5).

Each side is Blue Area (which is really called the Water Colume) of 8.75' plus 41.25' of bottom contour side image for a toal of 50 feet.

Also for folks that are wanting to learn more about Side Image you might want to check out http://groups.yahoo.com/group/sideimaging/

Register and look at the Files section, Database section and photos section (in the photos section also look at last photo folder called "z MESSAGE BOARD IMAGES").

Lots of good SI information on that site.

Right Mark.

John V. you are correct, you often see both side of the same object or group of fish. That's also both sides of the same log on the bottom.

Mark,

That is what I meant by 17.5' of blue (water column). But I should have split the 17.5' like you pointed out to get the true total length of the sideview for both left and right.

Varner's interpretation is what I concluded after Ernest pointed out the log was the same. The fish on both sides as indicated are the same school but it brings me to an interesting question.

The question is if the fish are clearer on the left side of the graph/pic than the right side as indicated in the graph, does that mean the school of fish is more aft to the port side of the boat than starboard?

This is interesting and confusing at the same time. Thanks to all for input/corrections.

Ernest that's the best explanation of this unit that I've seen thanks for taking the time to show us how it works.

Yes I believe if a tree trunk or fish (or any single object) is clearer on one side versus the other then that object is more so on that clearer side rather than the other.

But here is another interesting point, I believe you're seeing more of the bottom than just the outside of that water colume. Just look at that laydown log (or near the bottom laydown log). It's shown in both sides. When I first got the SI, I thought SI had a pretty big hole right under the boat that your not seeing (basically not seeing the bottom for the width of the water colume, in this pitcure 17.5'). As you can see that is not really the case. I think you see much more of the bottom directly under boat, pretty close to the center of the boat.

This unit sorta makes you wish you had paid more attention in school, or just hadn't been born so dumb. But, if you're gonna be in 'play', you gotta have one, or at least that's what I keep telling myself when I see that $2000 hole in my pocket

If you want to camo your condo from sonar, use similar concepts and technologies which the Skunkworks uses on their stealth airplanes. I.e. sonar absorbing materials and odd angles to deflect sonar away from the receiver. You will be pleased with the results.

List of don'ts:
-use PVC
-make condo's too dense or cluttered
-use items with a hard large surfaces
-use branches
-use buckets
-make them tall
-use right angles

My condos don't show up on Lowrance units. On my Humminbird unit, it looks like a very little rock. On my sI, they don't cast a sonar shadow.

Best part, they are cheap and so small that they hide very well in my boat so no one can see me taking them out. Takes only a minute to deploy. It is VERY easy to tell when fish are the structures in one or two passes. It's funny to watch others come over and circle...and circle....and circle...

Sorry, the rest is secret!

This stuff is harder than Japanese arithmetic.

Ha! I like that, Stelth condo's.

The opposite is true, if you want your condo to show like a neon sign on your sonar, use 2” or larger PVC which you make water tight before sinking. Sonar won’t penetrate the air pockets. Use clamps and attach ‘bucket’ panels to the arms of the condo. Not only to provide cover for the fry but angle panels to reflect your sonar beam back to you.

If this fails and you still lose your condos just attach a float to it so you can find it again.

Ya, I am not a total dumb arse still cant spend 2 grand on one though

Sabot,

Sonar (ultrasound) is transmitted as vibrations exchanged between molecules of water. Water is the carrier medium until it strikes a substantial change in density like the bottom or other dense surface including construction materials for condos. PVC and most other solid materials are reflective of ultrasound whether or not they have air or water inside. Much of the sound wave energy really never makes it through the surface of the material. Most would be reflected by the PVC surface. The rounded surface of PVC pipe would tend to scatter the return signal though.

Radar is looking for a change in dielectric constant in order to have a reflection. Radar also requires no molecular medium for transport. For example, bunker fuel and diesel have very low dielectric constants around 1.5 to 2.0 making it difficult to use non-contacting radar for continuous level measurement in tanks. The dielectric of air in a vaccum at 20 degrees C is 1. Dry Portland Cement is from 4 to 6 and reflects fine with high frequency modulated continuous wave radar. Water is very reflective with a dielectic of around 60 to 70 depending on various factors.

Active sonar will reflect from most all typical underwater structure that has a density different than water. The amount of sound energy returned is determined by the coefficient of reflection.

There may be ways to make something underwater harder to interpret via side scan sonar but less reflective to sound would be quite difficult for an average underwater application. All that stuff you listed would make it harder to interpret. However, if there is something in the water that is different than than bottom, and it has fish around, I'm certainly gonna make a couple of hi-res 800 kHz passes at a low distance setting, using a marker bouy as a reference point.

Just killing time. Have fun fishing!

Great info man!

I have not had luck in making a total stealth condo, just reducing it's signature. I am more carious on experimenting then making a farm of “Stealth Condos”. For me, the research and experimentation is part of the over all fun. The idea is to hide the condo during the off season but when there is fish on it, it won't matter to a degree. Chances are, most pass by thinking the fish are suspended. The credit of the air idea came from some discussions I had with Greg (@ Humminbird). I tried it on a few condos, it seemed to really help seeing it. It a bit costly to build the condos so I am not going to make any more. The lake I fish on (Granger) has a really soft bottom, which eats up my 800 kHz waves. I have been have much better luck using the low res. I have better luck using the high res on another hard bottom lake.

Have any more time to kill? Your info gave me an idea for another stealth condo. <Off to the Skunkworks Jr. workshop! > This squid technology stuff is interesting. Maybe I should have joined the Navy… Nah... I was born with Tanker boots on...

One thing about the Humminbird units, they are very user friendly, right out of the box. The install is the hardest part. If you know how to use a TV remote, you can learn the sI.

Have a safe flight home to your snowy wonderland!

Boy, am I glad Sheldon is my friend. Next time we go fishing he can tell me what he said in "Redneck speak". I know he speaks it cause he's from Arkansas.

Bottom line is, the condo is there, it will show up on most any graph and it's loaded with fish. What more do I need to know? Find it and fish it, I don't mind sharing. (anyway I have about 80 others to check on)

i am still using the factory set settings on mine. I just turn it on , and go. Havent gotten into the advanced stuff yet... summertime will force me too, though.

Aahhh, what Sheldon said....I do it all the time....I guess

I have tried different color screens and change the frequency between 455 and 800.

i have the 987, so i run a different frequency.

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