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Which Color Depthfinder Distinguishes Fish Species?
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Which Color Depthfinder Distinguishes Fish Species?
I have a Lowrance X 85 which is a super black and white unit. I can sometimes tell what species in under by boat by the shape and location of the image, but it is mostly a guess.
Which finder is really good at telling one species from another by the different colors that represent them.
My friend has a Furuno CRT that is about a year old. I run his boat often, but cannot distinguish fish species. Another buddy is running a new Lowrance LCD finder, and he has not figured out how to distinguish species yet. In fact if the gain is too high, he has beautiful "fish" marks when there are no fish. He is still learning to use it.:
Which Color Depthfinder Distinguishes Fish Species?
Are you kidding me?
The answer to the question is undoubtedly a $500,000+ side swiping sonar system used by the US Navy on submarines or possibly the guy who searches and finds all the old sunken ships(like Titanic).
BUT, your $500 or even 1 or 2 thousand dollar fishfiner is NOT going to tell you anything about what kind of fish is under your boat. You'll be lucky sometimes if it can find the bottom under you boat!!
In anycase, by far currently the most high definition consumer FF on the market right now is the Raymarine Digital unit: DSM250
Which Color Depthfinder Distinguishes Fish Species?
Thanks Birdman-
Will look at the DSM 250.
Fished with a captain in the 80's out of Fortescue NJ. He had a background in electronics and always had the latest stuff. His color CRT unit back then could distinguish fish species. I remember sharks were blue and sea trout were violet. We caught what we saw on the meter. Do not remember what make or model it was.
I imagine we are light years beyond what was available 20 years ago. F
Which Color Depthfinder Distinguishes Fish Species?
Species identification is also important to me because when describing the one that broke the line after 30 minutes of fighting, I would like to add more factual information to the stories I already tell.
The views and/or opinions stated by the author in this post are the views and opinions of the author
Which Color Depthfinder Distinguishes Fish Species?
Heres a nice feature for next year's sonar models. A little text box beside each clearly visible fish, of course displayed in 3D real time, with weight, species, and time since last meal.
Product Engineer, SMITH Marine Products, 21 Seacat, 2500HD Duramax/Allison
Which Color Depthfinder Distinguishes Fish Species?
quote:Originally posted by Think Tweiss:
Species identification is also important to me because when describing the one that broke the line after 30 minutes of fighting, I would like to add more factual information to the stories I already tell.
ThinkTweiss,
Adding "factual information" would pretty much complety kill any and ALL of my stories!!
Which Color Depthfinder Distinguishes Fish Species?
Wild Bill ,
Your New Jersey Capt. had a commercial fish finder. I had one, actually everybody I fished with had one. The machines asasigned a specific color to an echo's return strengh. Not sure but I think 10 to 16 colors where used. After alot of practice we would know what was going to come up in the cod end. It's been a long time but I think the going price back in the early 80's was 6k to 8k for the lower cost machines we used inshore.
Dave
Which Color Depthfinder Distinguishes Fish Species?
Think I am being ribbed a little here which is fine.
Still believe that some units can identify some species by color. A commercial hook and line friend of mine swears that sea trout have a yellow ridge around the image and other fish do not. He has a Sitex CRT that is at least three years old. One of the best trout fishermen on the bay.
I hesitate to put a CRT on my open Parker because of pounding and water issues.
Which Color Depthfinder Distinguishes Fish Species?
Bill I dont think you will ever find a sonar that you can tell which species you are looking at.Furuno proably has the best technolgy out their you can acutaly see your sinker hit botom with a furuno unit.As far as fish identifacation you can make a educated guess at what your looking at from what depth their at the size of the return and what your over.That comes from knowing your area and expierence.For example if I am fishing of the Ga. coast at A reef in the cooler months and see multiple images suspended at about 25 feet of medium size I am pretty sure it will be weak fish .Not from the display but from knowing thats the depth they like the structure they like and thats the way it looked last time I caught them their.
Which Color Depthfinder Distinguishes Fish Species?
Ok, here you go Bill your not crazy and my memory is beter than I thought.
Taken from the Furuno web site a partial descripion of Model
FCV-1500,
"A-scope presentation is also available on any mode so that objects just under the ship are evaluated in echo strength differentials at a glance This can be a special advantage to a particular fishing operation. TVG (Time Varied Gain)keeps the targets of same reflectivity at the same colors in different depths, offering the operator an easy assessment of fish species and distribution".
So technically you still have to ID the fish, the machine will show you different species in different colors.
Dave
Which Color Depthfinder Distinguishes Fish Species?
Thanks davidd, I do not mind being a little crazy--keeps life interesting.
quote:So technically you still have to ID the fish, the machine will show you different species in different colors.
That is exactly what I want to be able to do.
The NJ Capt who could identify fish by color was too good a fisherman to be BSing, and we became a friends. One year I chartered him 16 times. It was sad when the trout fishing went down hill. He sold his boat and went to work in electronics for Dupont. When he was searching for fish, I was normally standing right behind him looking at his meter. Trout were definitely a violet or lavender color.
Next Parker I buy will have an electronics cabinet and a color sounder.
Which Color Depthfinder Distinguishes Fish Species?
Wild Bill
I hear ya on the being crazy thing.
We used to call them a Chroma-scope or something like that.
We bottom trawled and after a little studying you could tell the difference between say a skate and flounder or if the bottom was full of spiders.
I am looking very seriously at Birdmans' reccomendation on the Raymarine DSM 250.
Dave
Which Color Depthfinder Distinguishes Fish Species?
I just bought the Raymarine L770D with DSM 250. Have not used it but 3-4 times and need more time with it. I think most charter guys with a multi-color unit can pretty much tell what kind of fish their over. But, it's mainly because they do it every frickin day.
Which Color Depthfinder Distinguishes Fish Species?
We had a similar thread a long while back, talking about how fishfinders work. A lot of skeptics piled on me when I was talking about how fishfinders work by detecting density changes, especially that of the airbladder. Experience certainly counts but that golden nugget of info provided by the airbladder reflection might be the ticket to have species identification right on the screen...
Which Color Depthfinder Distinguishes Fish Species?
Hey Preoccupation-
Piling on is the internet message board way. Goes with the territory. I know for a fact that some finders do distinguish fish species by color. Many hours with the machine is key. That was never my question. Just wondered which unit does it best.
Lefty once told me about a guy who was trying to tell him how to cast a fly rod: " He does not know what he does not know". True of a lot of internet chatter. You have to cull through it to get the good stuff.“
Which Color Depthfinder Distinguishes Fish Species?
Wild Bill, I've got a pretty tough skin about most things, and I enjoy a good debate as well...
About species identification...yeah, seasoned pros can tell what type of fish is on the screen...but the real trick will be developing the algorithms to tell the weekend angler what type it is...I can see it now...a huge project where different types of fish are pinged to build the database...should drive the PETA nitwits bonkers...
Which Color Depthfinder Distinguishes Fish Species?
Absolutly no fish finder distinguishes fish species by color.
The color represents the strength of the return echo, no more and no less. The time varied gain that you spoke of is a feature now included on every Furuno made. What it does in effect is segregate the range scale currently in use into zones and then each zone is assigned a fractional multiplication factor such that the deepest fish gets the pleasure of your full gain and succeeding shallower targets (presumably fish) will have the gain applied to them reduced. This gives the effect of treating all returned echos equally rather than showing a very faint return for even a hard target that was deep and a strong return for shallow targets even though they might be of creatures that normally show little to no return.
So the fellows ability to distinguish fish was really experience and not much of anything more. That said, it is also true that different species of fish give different return echos. Tuna are one of the ones that have no swim bladder and consequently have a very faint return. That would show up as a light foggy green on most machines, maybe even yellow. Some fish have very hard reflective scales and those fish will light up the screen with red returns every time. Bill fish will show up red too much of the time.
At any rate what you are seeing with the color is the relative (to depth) strength of the return from the fish. The fish itself does not have Caller ID to help this out. So for the Captain the naming the fish is very similar to using the fish finder for telling what sort of bottom you are over. Nice hard rock bottom will give you a distinct red line, grass, mud, silt, they give a much softer return and often even what looks like a false bottom as well. Sand can vary in my experience but mostly looks a lot like rock.
Which Color Depthfinder Distinguishes Fish Species?
So what you are saying Thom with your technical explanation is that fish finders absolutely cannot distinguish species by color, but experienced captains can take the color information from a unit and tell you what fish is represented. Interesting.
Which Color Depthfinder Distinguishes Fish Species?
Exactly. Folks who fish the same waters year after year know which species are present at what times of year. So its not like they were making their prediction on what they were seeing by selecting from every type of fish known to man, the types are always somewhat limited and you know how it goes. If all the marks you see for 5 years are yellow and 50 feet down and you always catch Dolphin, then its not likely you are goint to call a green mark a Dolphin. But then when November rolls around the same fellow sees that yellow mark, maybe a bit bigger, and now he says, Tuna. That's because he took a glance at both the temperature guage and the calandar too .....
Which Color Depthfinder Distinguishes Fish Species? 
