Question on Sonar

[dcfisherman]

I have a Humminbird 571 HD DI that is monochrome (black and white). Does anyone have experience using Black and white sonar units to locate catfish? I have a hard time identifying things on my sonar and basically just find areas that look like they might have fish. Usually I end up with nothing or one fish. I recently just figured out how to see my baits drifting on the screen, just confused about if if drifting over catfish or something else. I have watched Steve Douglas' videos on youtube and they have helped me a bit. I am still trying to figure out how he sets it to see the fish hit his bait...it looks like his chart speed is pretty high.

The pic attached is what I think is my bait drifting and some fish(?) next to it??

Any help is great!

[XxthejuicexX]

I run my Chart speed on 2D fast. Looking at the picture if the boat is moving I would say the solid line is your bait and the return on the right of the screen looks like a catfish. If you are sitting still the solid lines could just be fish hanging out under your transducer. I know you did not ask this but I will say get a color unit ASAP. You can find some for really cheap now, it will make your fishing life much easier. I'm always amazed when I see guys who fish often running black and white units.

[dcfisherman]

Originally Posted by XxthejuicexX

I run my Chart speed on 2D fast. Looking at the picture if the boat is moving I would say the solid line is your bait and the return on the right of the screen looks like a catfish. If you are sitting still the solid lines could just be fish hanging out under your transducer. I know you did not ask this but I will say get a color unit ASAP. You can find some for really cheap now, it will make your fishing life much easier. I'm always amazed when I see guys who fish often running black and white units.

I was moving around .5- 1mph and i raised my bait on that hump so you are most likely correct! well I was close that day at least I know now haha. Yes thats the next thing on my purchase list...well along with a jon boat. Kayaking has been great but it limits my possibilities. Deciding which one to get first is hard!

[Texas_Rig]

I use a black and white sonar and I can afford a color and ds and si. I would recommend turning up your sensitivity. It seems like a lot more clutter at first but you'll soon be able to distinguish what's there. I just started fishing a lot and seriously about 2 years ago. I know this sounds stupid and weird and probably is both but I think using cheap electronics has made me a better fisherman. That was my goal before purchasing a good unit. It makes me rely on my instincts first and sonar second. That will change I'm sure when I get a good unit. But it was important to me to establish that first

[dcfisherman]

Originally Posted by Texas_Rig

I use a black and white sonar and I can afford a color and ds and si. I would recommend turning up your sensitivity. It seems like a lot more clutter at first but you'll soon be able to distinguish what's there. I just started fishing a lot and seriously about 2 years ago. I know this sounds stupid and weird and probably is both but I think using cheap electronics has made me a better fisherman. That was my goal before purchasing a good unit. It makes me rely on my instincts first and sonar second. That will change I'm sure when I get a good unit. But it was important to me to establish that first

Gut feelings are definitely important! I was leaning toward buying the boat first because that will up more opportunities and areas to fish. Then a better sonar unit. I will try turning up the sensitivity next time and see what happens. Do catfish appear as a lighter gray on the screen? I have heard this because they do not have hard scales so its a softer return

[XxthejuicexX]

Originally Posted by dcfisherman

Gut feelings are definitely important! I was leaning toward buying the boat first because that will up more opportunities and areas to fish. Then a better sonar unit. I will try turning up the sensitivity next time and see what happens. Do catfish appear as a lighter gray on the screen? I have heard this because they do not have hard scales so its a softer return

From what I see on sonar is the head of the catfish is thicker/shorter and usually a stronger return and then the back section is lighter and thins out as the arch drops off. What I have heard is the head is wider and more dense so you get the solid return and then the rest of the body is softer so it's a less solid return.

[dcfisherman]

Originally Posted by XxthejuicexX

From what I see on sonar is the head of the catfish is thicker/shorter and usually a stronger return and then the back section is lighter and thins out as the arch drops off. What I have heard is the head is wider and more dense so you get the solid return and then the rest of the body is softer so it's a less solid return.

Got it. Sort of like a tadpole shape with a solid head and softer trailing tail

[XxthejuicexX]

Originally Posted by dcfisherman

Got it. Sort of like a tadpole shape with a solid head and softer trailing tail

Kind of. You can see what I'm talking about here.

[JKTrevecca]

The sonar shoots down in a cone shape. Think of a caution cone at a construction site with your boat at the top and the bottom of the lake at the bottom. You're able to see more information the closer to the bottom of the cone the objects are because the area of return is much wider at the bottom than the top. Something that is visible in 20 feet of water might not be in 5 feet because it is outside the cone width up higher towards the point of the cone. If a fish or any object for that matter, is directly under the boat in the middle of the cone, the return/echo will be strongest with no trail of the arch to either side. It will be an even arch. If you see one of the arches on your screen trailing off to one side or the other, it doesn't have much to do with the shape of the fish. It's more about the fish being off to the right or left side of the cone area below the boat. A fish on the right edge of the code will have a different echo return than one on the left edge and the two fish/objects will show a stronger return on the opposite sides of the arch regardless of what they are. This is true for a basketball or a fish. Doesn't matter. The arch is the result of the object moving through the cone or the boat moving over the object essentially moving the cone over the stationary object suspended in the water. I'm sure there are some very well seasoned graph readers out there but to my knowledge, few if any can determine fish species based on the shape of return on the screen. Somebody educate me if I'm wrong.... please!

[Heiny57]

Originally Posted by JKTrevecca

The sonar shoots down in a cone shape. Think of a caution cone at a construction site with your boat at the top and the bottom of the lake at the bottom. You're able to see more information the closer to the bottom of the cone the objects are because the area of return is much wider at the bottom than the top. Something that is visible in 20 feet of water might not be in 5 feet because it is outside the cone width up higher towards the point of the cone. If a fish or any object for that matter, is directly under the boat in the middle of the cone, the return/echo will be strongest with no trail of the arch to either side. It will be an even arch. If you see one of the arches on your screen trailing off to one side or the other, it doesn't have much to do with the shape of the fish. It's more about the fish being off to the right or left side of the cone area below the boat. A fish on the right edge of the code will have a different echo return than one on the left edge and the two fish/objects will show a stronger return on the opposite sides of the arch regardless of what they are. This is true for a basketball or a fish. Doesn't matter. The arch is the result of the object moving through the cone or the boat moving over the object essentially moving the cone over the stationary object suspended in the water. I'm sure there are some very well seasoned graph readers out there but to my knowledge, few if any can determine fish species based on the shape of return on the screen. Somebody educate me if I'm wrong.... please!

That is what I have been told and have read.