I get asked all the time at the sporting goods store I work at about depth finders and or fish finders. At the store we sell a variety of different brands and models of the units from the cheap $100 units up the high end $3000 plus units. So do I really need one of these for my boat and for my fishing trips?
Usually the first thing I ask my customers is, “What type of fishing do you do”? What I’m trying to do is determine what unit they may need for the type of fishing they will be doing. In asking this one question I can determine if they will be fishing for crappie, catfish or bass fishing. Then I ask my next question “Do you fish the banks or off shore?”. This question will let me know if they just need a depth finder to determine the depth along the shore line, in shallow water or deep water.
Stumps with fish – Sonar versus Side Image
After I get the answer from my customer I will start to explain in my opinion what unit the customer may need. If they are going be fishing along the bank just fishing shore line cover such as piers, fallen trees, rocks or other cover on the banks then they will not need a unit in the high dollar range. They would only need a depth finder to show them the depth of the water directly under their boat. If they move into shallow bays or coves it will let them know if the water is too shallow for their boat. As they move from one fishing spot to the other they can use the depth finder to make sure they don’t run aground in water too shallow for their boat.
Soft bottom – Dark, Hard Bottom -Bright Green and Red
Now if the answer I get back from my customer that they “crappie fish” I’ll then start showing them the upper end units with “Down Imaging” and “Side Imaging” capabilities. With these units they will be able to slowly scan the water out both sides of their boat. By doing this they can look for bottom hardness changes (mud, muck, rock, gravel or shell-beds, etc.) by looking at these changes this determine where the crappie will be fanning out their nests for the egg laying process. Fish do not like or live on mud or muck (decayed matter) they prefer hard bottoms such as rock, gravel or shell-beds. They can also scan the surrounding area for stumps, tree-tops, man-made brush piles, stake-beds to name a few cover options.
If I get back that they will be cat-fishing then I may suggest that they purchase a “Down Image” unit only. In most cases they will be fishing deep to very deep water for catfish. With the “Down Image” units they will get a very clear image of the bottom under their boat and out to the sides when looking for the fish they are after. These fish hold close to the bottom and are usually much larger than the other fish species and are easy to see. By slowing idling around in the deeper holes on the lake they can look for these large fish and know where to drop their baits in hopes of catching these fish.
Down Image – School of suspending crappie.
And finally if I get back that they are going to be off shore bass fishing such as the well known ledge fishing, then I will recommend they purchase the upper end “Down and side Image” units. With the higher end as well as higher priced units they will be getting larger screens, more powerful processors, higher pixel count screens, different mapping options and recording settings on their units. With these units my customer will be able to take advantage of all the bells and whistles of the high end units. With these larger screens you will get more pixels per inch which means a much clearer image on the screen. You can pick out smaller objects out to the side which can in some units reach out to hundreds of feet out both sides of your boat. With higher pixel counts you can get image separation of down to 2.5” on some units. This allows you to see fish holding closer to cover such as tree tops, stumps, piers, bridge pilings to name a few.
Sunken tree with my Side Image unit.
So as you can see, there are a lot of options out there when choosing a depth finder / fish finders. So I hope you understand a few of the reasons I will be asking you “What will you be using the unit for?” I’ll be adding more articles with tweaks, reading and image interpretation in later articles.