If you can get your transducer focused to where your fishing you can "see" your jig (or sinkers above a minnow) and watch how fish react to it. I have my transducer "shooting through the hull", which is about a 15-degree angle. It's near the front of my boat and it "views" the area where my front two poles are fishing.

A few weeks ago I told the kid watching those two poles that there were two fish rising to his bait and a second later both floats went under and we caught both fish. A lot of times I'll see fish rise to the bait and not take it. When they do that a couple times I'll drop the bait 6-inches to a foot and see if they take it then.

I can also usually tell difference between small bass or bream and crappie. Small bass and bream move up and down a lot more and a lot faster than crappie do and there are usually three or more in a group. Crappie usually change depth very slowly and I usually only see one or two come up to a bait at a time. I can get a pretty good idea of the size of the fish too, partially by the thickness of the return but also by the color. Small fish are blue/green, medium size fish have yellow in the middle of the return and big ole gar are nearly solid red. If your sensitivity is too low you won't see the smaller fish and the bigger fish will look like small fish. If your sensitivity is too high everything will be dark (or red or whatever color signifies a loud return on your particular graph/palette), including the fish and the cover they are in and around so you can't tell what's what.