Getting your graph set properly is getting easier with the evolution of better electronics. Many of the newer graphs will draw great pictures without changing a setting. However, most of us will want to tweak our units whether they need it or not.
There are really only a few things that I believe are important to tweak a graph. They are the mode, sensitivity, and range. I will discuss these in further detail.
Mode
Most units have an automatic mode and a manual mode. On most of the older units, either you let automatic mode do everything for you or you did everything yourself. Many of the newer units allow automation of separate components such as sensitivity and range. I believe this is a big step forward.
If your only option is manual or automatic mode, I recommend using the manual mode in most cases. The exception would be if you are learning the terrain and automatic mode is the only way to get the range to change with the terrain.
Sensitivity
Raising the sensitivity will show more targets, but will also show more noise and clutter. Lowering the sensitivity will show less clutter, but may miss some targets. I recommend that you have the sensitivity at least high enough to produce a double echo at twice the depth. For instance, if you are in 20 ft of water, set the range to at least 40 ft. If you don't see the bottom at 20 ft and again at 40 ft, increase the sensitivity until you do. Once you get it set, then set the range back to the appropriate depth.
Range
I like to have the range set to exactly what is under me. For instance, if I am in 20 ft, I like to have a 0 to 20 ft range. Unfortunately, the units I have used do not range as I would like. In manual mode, if you have the range set for deep water and then you go to shallow water, you will only be using a portion of the screen to display the entire cone. On the other hand, if you are set for shallow water and you go to deep water, you won't see the bottom without readjusting the range.
The older units only range automatically in automatic mode. The problem with that is that in automatic mode you lose all your manual settings. I have the newer units with the auto range feature. This is a great feature since it doesn't change my other settings. However, it still falls short in ranging exactly as I would like.
I have a graph on the front of the boat that doesn't have a 15 ft range. So, if I am fishing in 14 ft of water, I have to manually set the lower limits to that depth. It can be a chore, especially if I go back and forth between shallow and deep. I prefer to keep the lower limits as deep as I plan to fish. If I know I will be bouncing back from 12 to 18 ft deep, I will set the lower limits to 18 ft. I don't usually do anything with the upper limits, because I never fish deep enough to matter. You probably need to be fishing 50 feet or more for that to be an issue.
Annoyances
Annoyances are what I call features that don't serve a useful purpose. I'm not going to mention them, because there are more of them than useful features. If you ask me, the sonar companies could have made things real simple. If they had a sensitivity up and down button and a range up and down button, that would be all we really need. Wouldn't that be neat to just push a button rather than scroll through a bunch of useless features? I guess if they made them that simple, you wouldn't be reading this.
My plea for improvements
I tried to make my articles generic for all sonar suppliers. However, I would like to note that I use Lowrance electronics because I have been using them so long and they seem to improve them a little bit every year. However, their units have issues that I believe should have been corrected years ago. It is my desire that Lowrance (and other manufacturers as well, though they may not have these issues) take the following actions to greatly improve their units:
- Give us 4 useful buttons (range up, range down, sensitivity up, and sensitivity down). Don't make us scroll through a menu to get to them.
- Give us an automatic range feature that doesn't waste precious pixel space. Make 18 ft deep show up on a 20 ft range (not 60 ft).
- Give us a 15 ft range. If you can do a 5ft range (which is really useless), surely you can do 15 ft.
If you agree with me, please copy and paste the request and send an email to lowinfo@lowrance.com Maybe if we bombard them with requests, then they will fix their units in future years.