View Full Version : New to LCX111 need help indentifying sonar. PICS!!

03-07-2007, 11:57 AM
In these pic's I am fishing fresh to brackish water in the delta for White Sturgeon.

DEPTH: * * * * * *30 to 60 ft.
SENSITIVITY: *80 to 90%,
PING: * * * * * * *100%
UP & LOWER RANGE: Top either 10 - 20ft. Bottom roughly 10 ft or less below the bottom.
Transducer: * * Stock transom 600
BOAT SPEED: * 5 to 7 mph.
I was told that with this unit my target specie (4 to 6 to 10 foot fish) who only feed on the bottom (hense why I decided to cut out all above screen) that a target this large would be hallow and may not have much of an arch and color wise on a LCX unit would be full of yellow?

These pics are actual pics created after viewing my sonar video recorded trip of the night before last.
Just trying to get an idea on how to identify size of suspended objects either slightly above or on the bottom. I also want to be able to get an idea of size and be able to determine specie based on size?

http://img338.imageshack.us/img338/2978/sonarpaintpostanchorkq1.jpg (http://imageshack.us)

In the above pic the marks are very arched and a little yellow but not a lot. Do they seem like they can be the return of a 4 plus foot fish? Also, if you look to the Right you can see my anchor drop below them.

http://img109.imageshack.us/img109/7597/sturgeonpaint42posthm6.jpg (http://imageshack.us)

In this pic above it appears to me to be a large group I picked up off of a ledge?

http://img338.imageshack.us/img338/6388/lonesturgepostms7.jpg (http://imageshack.us)

In this pic is another large mark most likely a little larger than the other 2 scenarios I anchored below and the largest of the night for that matter.

Thanks in advance. I am going from a little 7" (Lowrance 350-A) monochrome screen to this 10.4 color and I am just trying to get caught up to the new millennium. *lol, ZACK!

http://img337.imageshack.us/img337/3108/mareislandsturgpostxb0.jpg (http://imageshack.us)

03-07-2007, 01:43 PM
i feel your pain
i rehooked up my old b/w sounder to help me determine what my new colormachine was trying to tell me
i keep the book handy and reread sections when confused
sometimes it confuses me more


03-07-2007, 09:24 PM
at that depth the best trick to do is to lower a swim bait about
the size of a blue gill then lower another one like a 5lb bass....
you simply have to jig it up and down a bit and read the scope...
it will show you the size and you will better understand the size.
I will on salt water sometime lower my lg swim bait 10" to see
the relationship as to what I am marking just to make sure...
even a large flasher 10" will work to...

03-07-2007, 10:13 PM
It looks like your colorline is a little too high and your sensitivity is a little high. I have an LCX 26C HD and I keep my sensitivity at around 75% and my colorline is about 85-90%. You can tell size by your depth range scale depending on your zoom.

03-08-2007, 08:22 PM
It looks like your colorline is a little too high and your sensitivity is a little high. I have an LCX 26C HD and I keep my sensitivity at around 75% and my colorline is about 85-90%. You can tell size by your depth range scale depending on your zoom.

My sensitivity is actually closer to 80% and my colorline as for being too high is lower then what you have yours at? I took the Lowrance course at the ISE and they told me a stong return on a large specie of fish will be filled with yellow and I have found that any colorline setting above 70% gives just about every little mark a little or a lot of yellow. As for Zoom I put it at the lowest setting. I like the detail enough already once I cut the depth to roughly 10 feet above the bottom and 5 feet below. Have you updated your unit and GPS reciever? I did the unit a while back and I did the gps last night. ZACK!

03-11-2007, 02:29 PM
Since fish finders work on objects that are a different density than water, and a fishes body is the same density as water, the image you see is the result of your signal waves bouncing off of air in the fishes bladder.

In order to know the size of the fish you need to have an idea of what fish are around, where you are fishing. You also, need to know something about different fishes air bladders. Some fish don't have much in the way of an air bladder so a 25 lb salmon will only make a dot on the screen. Rockfish show up pretty well

Another factor is boat speed. Since the start of the arch the tip of the moon so to speak is the first signal coming back as you approach the fish, it is further away than the signals you get when you finally get directly over the fish, the fat part of the arch or moon is where you are directly over the fish and then you get the other tip as you go away.

Now, add in the next complicating factor, the depth your sonar is set for and the depth of the fish. A small fish will look bigger than a big fish if the small fish is nearer the transcucer (shallower).

So, your question is good, but the answer is complicted and requires more information than most of us know. I've tried to reseach this some but there is a dearth of information on it. For instance I've seen what people swear are sturgeon on the fish finder, but I don't know if they have a bladder or much of an air bladder, but then maybe their bones are different and cause the sonar to work. Go figure!