Beginner question about sonar vs. down imaging

Is the down imaging considered a fish finding process like the basic sonar? Or is it really for viewing structure and bottom contour? I am learning to use my 570 DI a little better each time out but some things just aren't clear to me yet. I seem to be finding fish pretty regularly now sticking with the sonar setting and views, but they just aren't showing up well on the down imaging views.

I'm most likely going to be fishing a new lake that is relatively shallow, 16-18' at the deepest. With the sonar I'll only be seeing around 5-6' at that depth, less in the shallower areas obviously. I'm hoping the DI wider, narrower beam will cover more ground for me for locating purposes, but since I'm not really seeing the fish on the DI, I won't know when I've passed over them.

This unit doesn't show stuff like I see in the top SI/DI forum pictures. Not even close. But I'm getting happier and happier with the sonar results.

I'd appreciate some thoughts and sugggestions, but go easy on this beginner, please!

I'm still learning the DI and SI game myself, but from what I've read and actually seen on my Lowrance 8 package, DO NOT be afraid to change the settings. Punch them buttons to change the picture in terms of color choices, contrast, range, etc. You can always change the settings back. Changing the palette color(s), contrast, etc., will either sharpen the picture you are seeing or make it worse, with no harm to anything other than another fingerprint on the HU. Changing the settings will/might make something appear that didn't when viewed or seen with the previous settings.

DI will not show "fish" like a 2d sonar will (either an arch or fish symbol), they show up as white dots and that's about it. DI will show the detail of the "structure" that looks like a blob (for lack of a better term) when in 2d mode. You'll see the individual branches/limbs/main trunk on a submerged tree/brush pile, or the individual stalks of weeds/grass, etc., depending on the location of the TD in relation to the object. Circling around for another look at something from another angle is always good, it may show more or less but you'll get a better picture of what the object is. The fish will then be a white dot in or around the object(s) being scanned. DI will also show contours in the bottom with much more detail than 2d will just because of the more narrow/stronger(?) beam it uses, where you should be able to see alot of the nooks and crannies that may attract fish.

DI will not replace doing some research on new water, look over the maps before you hit the water, so you'll have an idea of where the drop offs, creek channels, stump fields, etc., are and then you can focus more on finding the fish in those areas. Look over some of the pictures other people have posted, some post the 2d version and the DI version so you can see what the differences are between the two.

The 570 is a black & white unit only so the color changing is out. I don't have any of the card slots or screen capture options; the 570 is a pretty basic unit. It does have contrast and some image shading options. I've been using it all summer on my trips and have been tinkering with settings. I do appreciate the detail it provides on structure below; I've been able to see individual leaves on stalks and stuff, and pretty darn good detail of bottom items so it is doing its thing pretty well in that respect. I just wish it was easier to see fish in that DI view. But it does see them like the sonar does, eh? That's helpful to know. In your opinion, do you feel the white blobs of fish in the DI view should be clearly defined, not neccesarily fish shaped but recognizable as a beam return and not a ghost image? How about depth of water before the DI loses power or definition when on the 800 vs 455 settings? Any thoughts on that? They mention that in the owners manual but don't offer anything like "use the 800 beam down to 35' (or 15 or 10 or wherever the line might be) and use 455 below that" to give a sort of guideline as to where one beam peter's out depth-wise and the other really shines. Actually, that owners manual is kinda useless for the new, inexperienced owner, in my opinion. I've got the fish alarm and fish ID off based on my reading of this section of C.com. I've run and played with the demo mode quite a lot, too, and that's helped me get some of the better 2D performance I'm currently getting.

DI is great but as stated the fish won't show up as arches. Instead they will show up as little dots or ovals. Mine is a color unit and I've never messed with the b&w version but I would think you would see the fish as little black dots and specks within or near the structure. You may be seeing fish now but don't realize it. They should give a solid return like a hard bottom does.

the fish will not be a clearly defined as the structure itself. I would guess that is due to the fish are probably moving/not completely stationary while the stumps and trees are except in strong current. 455 vs 800 depends on depth and you'll just have to experiment with which frequency works best in the different types of water conditions you encounter. Again, don't be afraid to punch those buttons, if you can run the spilt screen on your unit, showing 2d and DI at the same time, compare the 2 screens to see what each is telling you and if you are coming to the same conclusion from each screen.

Wait until you get SI, and then see the "shadows", that's another whole game to play then. LOL