It would be great to fully understand the info shown on the DI screen.
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It would be great to fully understand the info shown on the DI screen.
Bryan what specifically you need to know?
When I get my new boat it's on the list but DI is pretty simple> Set it to Wide and 455kHz and Adjust Sensitiity to your liking.
Well.... when you look at the display, you can see things (rocks etc.) not on the top line. Is the DI display a flat picture laid on it's side (for lack of an easier way to put it)?
Does that make sense?
Bryan, Watch this video by Doug and all things will make sense.
http://www.youtube.com/watch?v=3xe6pLPdMKc
That's the SI view and I understand how that works. I'm talking about the DI view.
http://i36.photobucket.com/albums/e6/imonem/S00002.png
Look at this image. Since DI has different coverage areas like narrow, medium and wide most are using wide so you have data coming in from a larger area. Like this image. I've marked the corresponding data in both DI and SI. DI is showing straight down data only. This is one of the greaet features of SI is that you can tell exactly where the data is coming from - right or left. With a wide area of coverage with Wide DI seeting you are getting so side data so it will display it away from being on top of the bottom like you are asking? DI will show everythign that is in SI but changes the way it's viewed from a top down view versus side to side.
Does this help?
So, when you're looking at the DI image, things on the "top" for lack of a better term are directly under the boat. Is there a way to determine which side of the middle the rest of the stuff is on? Hard to put into words what I'm trying to ask...
I was thinking the same thing. Seems like they should be able to show the view of the bottom just as the transducer is "seeing" it, looking straight down in a 2d view, then have a screen showing the water column to show fish, structure etc. in the water column. I just don't see in that shot how you tell left from right so to speak.
I was looking at it all wrong, I see now. It takes a little while for my brain to start working. That big rock is the "center", and then you can look the way doug has all the others marked and tell which ones are on the left and right. http://xs-s.com/zf/images/smile/emthup.gif http://xs-s.com/zf/images/smile/emthup.gif
Bryan, The Sonar and DI show the "same" thing but DI covers a greater area but in a different format.
Here is a "rough" drawing I did to show DI beams (wide, Medium, narrow) vs Sonar beams.. FYI the footprint of DI is a narrow line unlike a narrow oval as I show it.
http://i123.photobucket.com/albums/o...idualfinal.jpg
Figure the 200/83 dual beam being close to the dual beam with the Wide DI beam going beyond that. So it is possible to see things on DI and not on Sonar due to the wider beam.
The youtube video I showed you where Doug folded the paper.. When the paper is folded that is what you see in DI.. Go to the 3:15 mark on that video and see where Doug is folding the image and then compare it to this one....
http://i123.photobucket.com/albums/o...nar/S00135.png
Mike
Looking at Doug's image, the orange and white are on one side and the pink and blue are on the other side according to the SI image. The question is, how can you tell by looking at the DI only? I'm not seeing that part.
Modified by Bryanmc57 at 4:12 PM 1/27/2011
I see what you are saying. If the screen would scroll top to bottom like the si it would be a lot easier to understand. When it is scrolling right to left it's hard to tell if an object coming into view is on the left or right. My brain is hurtin......
<table width="90%" cellspacing=0 cellpadding=0 align=center><tr><td>Quote, originally posted by Bryanmc57 »</td></tr><tr><td class="quote">Looking at Doug's image, the orange and white are on one side and the pink and blue are on the other side according to the SI image. The question is, how can you tell by looking at the DI only? I'm not seeing that part. <br /><br />
Modified by Bryanmc57 at 4:12 PM 1/27/2011</td></tr></table>
Bryan, You simply can't tell from a DI screen alone on what side of the boat a tree is on. Same thing with Sonar you can't tell direction either. Now what you can do is use the narrow beam and narrow things down to directly below the boat but it still could be minorly off to one side of the boat or the other and your viewing area is reduced drastically. The only way you can tell what side of the boat a tree is on with DI is by either seeing it visually above the water or by using SI screen in conjunction with DI screen. Thats why I always say SI is KING when compared to DI in finding fish as it tells you almost exactly where they are and on what side of the boat and coves a TON more area. The only thing DI does for me when compared to sonar is to give me a better idea of what the structure looks like as close to a photograph as possible.. The down side of DI is it's a tough sell vertical fishing watching your spoon and dropshot unlike with 2D sonar due to the beam foot print 2D (circle) DI (straight line).
Thanks Mike, that's kinda what I thought. So in reality, the DI image really is sort of a flat SI image from directly under the boat (think of turning your unit flat and rotating it so the right side pointed towards the bow). The only drawback is that while thing right on the depth line are directly under you, there's no way to tell which side the rest of the data is from.
"I Think" you are right LOL. DI is a cool tool no doubt. Gives you a better visual of what you are seeing under the boat and in more detail than 2D but it has it's limitations. The system as a whole is what makes DI/SI and 2D what it is..
THat is the thing with Down Imaging and even 2D Sonar you can't tell which side the data is on. Now QuadraBeam 2D and SI have the ability to show you direction from the transducer. That's the huge advantage for Quadrabeam for 2D sonar and Side Imaging for High Frequency Sonar users. You can't tell where the data is in realationship to the transducer it's in the sonar coverage area but where?
Narrow mode ~ it's in 1/3 of depth area of coverage
Wide Mode ~ it in approximately same area of coverage as depth
Wide Mode ~ is approximately in an area 1.5 times the depth
Here's another one that I did on DI versus SI. Where are the trees located in relationship to the Transducer????
http://i36.photobucket.com/albums/e6/imonem/S00269.png
But Side Imaging adds another dimension and the ability to tell which side the data is from...
http://i36.photobucket.com/albums/e6/imonem/S00268.png
The ones on the depth line are right under the boat (confirmed by SI), the one under the depth line is off to the the left but no way to tell which side without SI.
So I guess the educated answer is "If it's on the depth line it's directly under you, if not, it's in the beam somewhere" Correct?
On another note, with the new contour mode in SI, it's kind of like a wide cone DI and will tell you exactly where everything is right? Or am I over-thinking that one?