I have a Lowrance x107c df. It was around a 700 dollar unit 6 years ago. Now discontinued and replaced with new technology
Broadband and downscan. This new stuff seems to be incredible although you pay for it. The unit I have has 4000 watts peak to peak.
The new lower end units are still rated in this way. The more Watts the more you see - again depending on the number of vertical pixels
Your sounder has. The fewer vertical pixels the more difficult it is to differentiate between objects. You can improve this by zooming into
A particular zone in the water column.
The biggest problem with automatic features on sounders is the fish I'D feature
It gets fooled quite easily by just about anything that is not on the bottom - you name it between a thermocline, algae, weeds, branches and trees that have fallen in to the lake.
The tuning part mentioned in previous posts includes turning off this I'D feature and then on a non- color sounder use grey scale, sensitivity is another auto feature actually can usually be left alone. Just to give you some idea a deep clear lake like alloutte when fishing say 200 ft - sensitivity Will be around 90% - that will decrease in shallower lakes and ones with more color like Sayers or folly. If sensitivity is left at 90% in these shallower lakes then you will have a lot of noise that will make it more difficult to see fish.
Once you have turned off the I'D feature - fish will appear as arches, partial crescents, or as straight lines if the fish is moving faster than the boat. Again there will be some trail and error- the easiest thing would be to find some fish to see what they look like and then the next time you will know. I know maybe easier said than done. When you get it figured out it's a real feeling of anticipation knowing there are fish that could be biting any second. Hope I started you in the right direction.