Fish ID Working Properly?

[BrownTrout]

How would you interpret the following image? This is a bow mounted Helix 10 DI Mega Chirp GPS G2N unit. It was taken along a bluff with 2D Chirp Display Frequency set on High/Medium frequency, Fish ID turned on, Fish ID Alarm turned on and Switchfire on Max. The bluff was approx. 10 ft off the starboard side. It appears that 95% of the fish were in the chirped 83 frequency and the alarm was really going off.



Here's the issues: 1 - when I switched from High/Medium to just High frequency, 95% of the fish disappeared and I have a hard time believing all those fish were in the 83 frequency and only one in the 200, 2 - after switching to Chirped 200, the Fish ID Alarm was still sounding off with NO Fish anywhere on the screen, 3 -never caught a single fish in that area. You'd think we would have foul hooked one or two, 4 - when I circled back and retraced the area with only Chirped 200, there were hardly any fish to be found on the screen throughout the entire area.

Makes me wonder so I thought I'd ask for opinions.

[Wayne P.]

All of the fish are within the coverage of Dual Beam, they are separated by the frequency. Looks like just one was under the transducer close enough to be in the high CHIRP coverage and the rest were off to the sides in the med CHIRP coverage. You just don't know how far to the sides those med CHIRP fish are unless you also use SI.

Sort of like this screen shot with three in the high CHIRP frequency coverage and the rest in the med CHIRP (along with surface bubbles) plus thousands of baitfish with no symbols:

[BrownTrout]

That is my understanding of how it works as well. But I don't understand why Fish ID alarms continued to go off with no fish on the screen after turning off Med sensitivity as I continued down the bluff. And why those fish that showed up on 83 didn't show up when I moved out from the bluff, turned around and scanned again with 200 only. Thought it might be a function of depth where the 83 could see deeper than the 200, but I was never deeper than 80 ft or thereabouts when I rescanned with 200.

I have an XTM 9 MDI T dual spectrum transducer on my tm and was using the Med and High beams.

[Wayne P.]

That is my understanding of how it works as well. But I don't understand why Fish ID alarms continued to go off with no fish on the screen after turning off Med sensitivity as I continued down the bluff. And why those fish that showed up on 83 didn't show up when I moved out from the bluff, turned around and scanned again with 200 only. Thought it might be a function of depth where the 83 could see deeper than the 200, but I was never deeper than 80 ft or thereabouts when I rescanned with 200.

I have an XTM 9 MDI T dual spectrum transducer on my tm and was using the Med and High beams.

Maybe the CHIRPer not being tuned to the CHIRPee was the issue.

I have not tried the mismatched settings.

[BrownTrout]

Well, I guess there were two CHIRPees out of tune yesterday.

By "mismatched settings" you mean the Medium and High frequencies together? Isn't that what you were using in your screenshot above? Used it all the time on my 998s, mostly when searching for fish.

Did you notice the depth of the one fish in the High freq range compared to all the other fish in the Med freq relative to the bottom shown on the screenshot? Bottom depth runs from around 25 ft to 35 ft. Fish are shown as low as 60 ft. Since I was close to the bluff on the starboard side in 25 to 35 fow, most of those fish must have been out in deeper water on the port side of the boat. Right?

[Wayne P.]

Well, I guess there were two CHIRPees out of tune yesterday.

By "mismatched settings" you mean the Medium and High frequencies together? Isn't that what you were using in your screenshot above? Used it all the time on my 998s, mostly when searching for fish.

Did you notice the depth of the one fish in the High freq range compared to all the other fish in the Med freq relative to the bottom shown on the screenshot? Bottom depth runs from around 25 ft to 35 ft. Fish are shown as low as 60 ft. Since I was close to the bluff on the starboard side in 25 to 35 fow, most of those fish must have been out in deeper water on the port side of the boat. Right?

Yes, but I was using a first generation Helix 12 CHIRP SI GPS transducer with a 83/200 kHz rated 2D crystal. XHS 9 HDSI 180 T.
Your 998 also had the exact same SI transducer.
There was no Dual Spectrum LowQ CHIRP transducer until the MEGA DI transducer for the G2N MEGA DI units and then the accessory MEGA DI transducer for the first generation SOLIX.

Have no clue why you were getting FishID alarms and no symbols, just guessing. I never use the alarm.

It's tough to figure what the overall screen shot indicates since it looks like the Sensitivity is way to high for the location.

I intentionally did not adjust the 2D Sensitivity in this screen shot since the DI performance is what I was interested in and the depth change was very rapid with a hard bottom (rock cliffs). The 2D is too hot.


When I got deeper, the 2D Sensitivity was closer (but still too high) to what it should be for the location, same area:

[Wayne P.]

Using the frequency that matches the Dual Spectrum Low-Q crystal, you only get the gold FishID symbols:

[BrownTrout]

Right. I had the Sensitivity turned way up for running. Seems like most of the 2D bottom problems I still have with v1.84 are minimized by cranking up the Sensitivity when running.

[MonteSS]

To me that screenshot is a disaster.

My Mega Si unit unusable on 1.84 so I use 1.64

Reset to defaults.
Only run high chirp
Clear mode
Lower range on auto
Surface clutter on 7
Sensitivity on 10
Contrast 20
Run split screen 2d/Di so the Di can verify what the 2d is showing.

I use this all day and never need to adjust it.

Try this. I can go as shallow as 4-5' and the depth wont jump.
This is on my trolling motor and works from 0-3 mph
I dont use Fish ID so cant help you there. But get this right first.

Be aware that on high chirp you get more of a blob than an arch.

S00245.jpg

[BrownTrout]

I am running v1.84.

Majority of my depth issues are when running and I usually run between 50 and 70. No real depth issues while trolling or fishing.

Tried lower range on Auto. HB Tech Spt told me to set depth to deepest water where I fish . So, it's set at 200. Tried it both ways and found no difference.

Sensitivity at 10 and Contrast at 20 is where I usually have it set. Sensitivity was much higher as I ran to the bluff and didn't turn it back down.

Usually keep Surface Clutter on 7.

What's the point of dual spectrum if you are only going to run High Chirp?

Idling on a small shelf alongside a bluff 10 ft to the right with depth falling off sharply to well over 140 ft on the left presents a challenge to any 2D unit and images are difficult to read. Same bluff with my 998 a few yrs ago below using 83/200.



You are right in that I should have used my DI to take a peek as well. SI is useless at those depths.

This next pic isn't along that bluff but details would have been more obvious if I'd switched from 2D to DI or split the screen as you suggested. My 11 yr old trolling motor has some slack which shows itself in this image when I hit the pedal and then let off.



Problem with DI in deep water is that fish are difficult to see. And fish is what I was looking for, not pretty pics. I never spoon off a DI or SI screen. Only 2D.

I've caught some really nice fish vertical spooning off this bluff in the past and always use Max Mode when spooning. Once I find the fish, I switch to 200 from 83/200.

Thanks for your suggestions!

[BrownTrout]

Fish caught off this bluff vertical spooning.