Trying To Learn The Language: Iron Nails Vs Masked Targets

[AirmetTango]

Apologies in advance for a very long post. I’ve only been using the Manticore (MC) for a couple weeks, and I only have about 15 hours on the machine, so I’m a long way from being a master. I’m coming from 5 years loving the Equinox 800 (EQ800) and 7 total years detecting experience. I’ve seen many comments from more experienced detectorists stating that the MC is really a completely different machine than the EQ800 - it’s not just a “souped up Equinox”. Despite hearing that, it’s hard to resist the urge to draw parallels and try to correlate my previous hard earned experience with what I’m seeing and hearing on the MC to try and speed up the learning curve….and maybe that’s why I’m running into trouble!

Like many others, I’m finding that I’m digging way more iron nails than I ever have with previous machines. Here’s the iron from my last few hunts, versus a total of $1.47 in clad and 4 Wheat pennies:

 

I don’t mean that I’m getting completely fooled - often the machine is providing hints that the target has ferrous qualities. I believe my problem stems from my hopes of unearthing a deep, partially masked coin. I don’t put a lot of stock into air tests, and usually don’t waste much time on them, but when I first bought the MC, I did a series of air tests to help me learn what the 2D screen might look like in various situations. The shape of the target trace on this particular set up stuck in my mind (Barber quarter next to a square nail):

 

Swinging over the above combination resulted in these pretty distinctive target traces:

 

I was pretty impressed with the 2D trace’s ability in the air test to clearly show strong evidence of a good masked target. Unfortunately, once in the field, I quickly re-learned that air tests don’t accurately reflect the behavior of old iron that has marinated in the ground for a handful or two of decades. It appears that every deep buried nail in existence creates the exact same target trace!  Here’s an example of the traces for a deep target that I hoped was a masked coin, but turned out to be a solitary, large iron nail:

In the case above, I was originally searching using sensitivity set at 20, using the “less is more” philosophy suggested in other posts to help avoid iron falsing issues. Once I isolated what I initially thought might be a good high tone target, I turned 90 degrees at sensitivity 20, and still had a centerline non-ferrous, but slightly skewed to the upper left. The photos above show me progressively raising the sensitivity…only at 27 did the target truly start to reveal what it really was…just a deep nail. If I left the sensitivity at 20, circled the target, and then dug, I actually would have been genuinely fooled by the nail. 

Here’s another field example of traces - this is the only one out of dozens that turned out to be a masked target…a clad dime co-located with a large iron nail. Again, my initial target discovery swing was while using sensitivity 20, and I raised the sensitivity to 25 as a checker to see if I could coax out signs of iron falsing (I might keep this permanently as a soft key). Honestly, the traces at both sensitivity settings looked similar, but all the photos were taken at 25:

As you can see in all of the photos above, I’m using ATHC, which is the mode most prone to falsing due to the very low frequency weighting. But I had the same experience using ATLC - I kept feeling enticed to dig each of these type of iffy targets on the hopes of uncovering masked targets, and instead coming home with dozens of iron nails and one clad dime for my efforts. Recovery speed was set at 4 throughout all hunts.

Don’t get me wrong - I’m not blaming the machine…it’s telling me these are iffy targets. I’m the masochist that’s deciding to dig all of them! Of course, all machines false to a degree, especially on deep nails. On the EQ800, I developed a technique that worked well for me - when turning on a deep target, if I had an iron tone at least 50% of the way around the target, I confidently walked away. If the high tone continued most of the way around, with say only 25% or less of the circle giving some iron, I would dig - sometimes I would still be wrong, but often times I’d get rewarded with a good target. I rarely came home with more than a one or two nails in my pouch, and rarely was one a complete surprise. 

With the Manticore, it looks like I may have set my expectations too high on what I can discern from the 2D trace regarding masked targets based on the air test traces. But also, the Manticore seems to high tone alert much more enthusiastically and more frequently on deep iron in general. With the EQ800 with F2 set at 1 or 2, I was stopping to investigate these kinds of “falsing/iffy” targets a handful of times across a couple hour hunt. With the MC, this is a constant task - every other swing is giving me a high tone to investigate and spend precious time evaluating…even as I learn to ignore these as falsing, it’s incredibly time consuming and eating into my enjoyment as they all inevitably get discarded as falsing, or worse, dug.

All this is to say, I’m looking for any advice from more experienced MC users to help keep the false high tones more under control, and better recognize a truly masked non-ferrous target versus falsing iron. Overall, the soil in my area is extremely mild, as determined by the mineralization meter on a Nokta Legend (consistently zero bars on the mineralization meter). I’ll try ATLC again, but my first few hunts were using that mode with similar results. Lowering the sensitivity doesn’t seem to be the answer, because I’ve actually had to raise sensitivity in many cases to get an iron response (traces in the grey zones) - otherwise many of these falsing nails would have looked and sounded dang good. Increasing my ferrous limits likewise doesn’t seem to be the right answer without completely eliminating the chance to hit on anything even remotely masked. 

Thanks in advance for any advice! 

 

[UT Dave]

It sounds like our dirt is pretty different.  So, not sure I could be of much help, really.

Curious how you are running the audio though.  Very much personal preference.  But I only run in 1 region all tones.  I find the audio tells of full tones helpful.  I do usually run ATHC in park turf.  But in iron infested ghost town sites I prefer ATLC or maybe ATG, specifically because I get fooled by iron less in those modes than ATHC.

In my dirt, running recovery at 4 is what I consider getting aggressive and less choosy about targets.  I almost always get tighter ID's at better depth running at 5 or 6.  Truly masked, is truly masked, and I don't know how to overcome that.  At 5 or 6 recovery though, what may often sound like a single target at 4, represents as two targets.  This is not what I'd call truly masked.  More like co-located.  But at this point, after using the Manticore a lot for well over a year now, I feel it's a good bit better at sniffing out a good co-located target than the 800 I used to use.

My dirt just won't tolerate the kind of sensitivity you are running.  About the only time I get over 20 is with the M8.

In a nutshell though.  My thoughts at this stage in my experience with the Manticore, I "tune" for stability and tight VIDs and let depth take care of itself.  If I'm bumping up the sensitivity and bumping the recovery speed down, it's because I'm pretty much planning to dig anything that sounds deep.

- Dave

[AirmetTango]

1 hour ago, UT Dave said:

Curious how you are running the audio though….

In my dirt, running recovery at 4 is what I consider getting aggressive and less choosy about targets.  I almost always get tighter ID's at better depth running at 5 or 6….

My dirt just won't tolerate the kind of sensitivity you are running.  About the only time I get over 20 is with the M8….

Thanks for the insight, Dave - lots of good food for thought here! I hadn’t considered the recovery speed being a factor. I chose 4 because that’s been my basic starting point on the Equinox. On that machine, it usually was the best combination of excellent depth while remaining fast enough to not notice any real decline in separation. Target IDs didn’t seem affected at that level, but of course the Equinox had a much more compressed VDI. Anyway, at sites with more significant target saturation and/or contamination, I’d bump it up a bit, but it was fairly rare - I would generally tend to opt for a smaller coil before going any higher than 5 or 6 on the EQ800. But it looks like it might be worth experimenting a with little higher recovery speed on the MC.

For audio, I’m using a slightly modified 5-regions All Tones. The most noticeable modification is the tone breaks - I have it divided into sub-nickel, nickel, trashy, IHP to dime, and quarter & up ranges. Less obvious is the flat tone range for nickels - I didn’t want a tone slope there because it was making nickels sound too iffy or less attention grabbing for my ears:

 

My sites so far have been public parks, but they each have a history of prior use that lends themselves to heavier than normal iron nail contamination. I’ll definitely try ATLC again - with my increasing knowledge of the machine, maybe I’ll find the iron falsing tendency will be less noticeable when I give it another try, especially when coupled with a different recovery speed.

Yes, my area seems to be better suited for higher sensitivities - mineralization is generally very low, and the MC does a fantastic job of killing EMI. I get pretty tight VDI numbers at sensitivities between 20-23 on non-ferrous targets uncontested by iron. VDI definitely seems to suffer as I get above 25. As I mentioned, I usually have to raise the sensitivity to bring out the iron range on many of these falsing signals. Lowering the sensitivity makes me concerned I would just get genuinely fooled more by tight non-ferrous tones and traces with no hint of iron. On the flip side, perhaps if I lower sensitivity into the teens instead, the falsing high tone iron goes away, but a coin/relic at a similar depth would still show up? I don’t have enough experience with the Manticore and deep coin/relic targets to answer that, yet. 
 

I agree, tuning for stability is key, and you get what you get on depth as a result. Up to now, I always just thought of stability in terms of EMI or lighting up too much micro iron at old home sites - excessive chatter meant I needed to back off sensitivity. The Manticore runs very quiet for me at 20-23 in most cases - I just have the constant occurrence of too many large nails masquerading as co-located non-ferrous targets. I suppose now I need to consider big iron/VDI stability, as well, and I need to drop sensitivity more than I think?

Lots to consider and experiment with!

[Skull diver]

33 minutes ago, AirmetTango said:

Lots to consider and experiment with

I hope I am not confusing you more, but I suppose it is worth considering another course of action.

I don't know how high your threshold is for a ferrous tone that repeats often, but with smaller ferrous limits under and above the 2D line first and an audio ferrous tone on pitch1, surely a "dirty" signal is much better distinguished from a non-ferrous, clear one.

Also about tones, I'm talking about using depth audio themes instead of single bins.

All metal and red numbers do a great job without dumbing down the instrument and still the screen indicates potential iron.

Also, the volume of iron equal to nonferrous enhances a signal worth digging much more.

By raising the sensitivity beyond 23 points, I have noticed that instead it is better to increase the separation rate to 6 in some cases.

Be prepared to listen to a very frequent ferrous grunt, but then tell me what happens in the same context....

[AirmetTango]

1 hour ago, UT Dave said:

…Truly masked, is truly masked, and I don't know how to overcome that.  At 5 or 6 recovery though, what may often sound like a single target at 4, represents as two targets.  This is not what I'd call truly masked.  More like co-located.  But at this point, after using the Manticore a lot for well over a year now, I feel it's a good bit better at sniffing out a good co-located target than the 800 I used to use.

 

And yes, thanks for making that differentiation! I kept saying “truly masked” in my original post, but I do just mean co-located ferrous and non-ferrous…not necessarily two targets that are too close together for the machine to truly separate into individual targets.

And maybe that’s the answer…my air test example above doesn’t represent true separation, because the machine was just seeing one target with confusing ferrous and non-ferrous qualities. Essentially a trashy single target. Just like a deep, large nail vs the surrounding soil matrix! Of course, in the field that’s going to be junk 99.9% of the time…might get purely lucky that one time in a thousand and get silver. 
 

Just tried those same two test targets in an air test, and pushed them a little further apart, and bumped the RS to 5:

 

Again, just an air test, so I’m skeptical if this will hold true in the field, but the gap between the ferrous and non-ferrous is consistent and noticeable…much more indicative of two distinct targets. Perhaps this is a “tell” for in the field as well? If there’s no prolonged gap after circling, walk away?

I’m probably just trying to read too much into the 2D trace again! 😄

[UT Dave]

FWIW, I ran my 800 at recovery 4 almost all the time.  Never above 5.  Testing on in the ground targets - my coin garden but they've all been in the ground at least 15 years now - I found I actually get better dig me signals with the Manticore at 5 or 6 than I do at 4.  And even more so with the update installed.  Absolutely not what I would have expected coming from the 800 and just one of the reasons I'm one of those who say the Manticore is not just a beefed up Equinox.  It really is a completely different machine.

Speaking of the update...  Running the Stabilizer on, at 1, I can squeeze a number or two higher sensitivity.  But I generally don't like what it does to the audio even at a setting of 1.  I never use the Stabilizer Filter - I hate what that does to the audio.  But I'm trying to get used to using the Stabilizer on, at 1.  Still kind of early for me with that to have a strong opinion.  Other than, I can go a notch higher sensitivity and maintain stability, which is why I'm giving it a go.

- Dave

[fishersari]

I think you need to let go on what's the 2d screen is doing for now and try to learn using audio only to distinguish between iron falsing, ground noise and iron especially if you using overdrive sensitivity.. I by no means an experienced detectorist..

In iron sites I'm using m8 too with enhanced audio/medium profile. For me enhanced audio help me with the targets (strongest tones = at the center of the coil) before I'm using the pinpoint function on that particulat target.. For sensitivity i run as high as I can before iron falsing usually 20-23 on M8 and 19-21 on M11 with recovery speed of 5/6. I think in iron sites the proper way to learn the machine is using ATLC > AT General > ATHC for my ground and without target trace and red number in the mix..

I lowered the bin for 98-99 because it does help me mellowed down the overall falsing tones and I'm not chasing high conductor.. our valuable are tin coinage in the range of 12 to 60 ID

Have you experiment with stabilizer?  I didnt use it but many of my detectorist friends use them and its help them a lot..

There's a response from Minelab regarding the falsing on Manticore before they released the update which I think its makes clearer picture of what the Manticore is all about

Edit: found the post.. copy and paste from

Excessive Falsing in Iron - Minelab Official Response.
I contacted Minelab and was happy to receive a very thorough reply:

***The MANTICORE is a very different detector to the EQUINOX, despite some similarities. It was specifically designed with heavily hunted-out sites in mind, which are now much more common for most detectorists, and where finds are becoming increasingly sparse. It is intentionally much more aggressive than the EQUINOX 800, and is designed to stop users on iffy detections more often, but also to provide the user with more information on which to decide whether to dig. We would expect an experienced MANTICORE user to dig iron more often than with an EQUINOX 800, but over time should also find some targets that an EQUINOX 800 might overlook. The consequence is that the MANTICORE can be a more challenging user experience, and we find that most experienced EQUINOX 800 users need to go through a period of adaption to get the most out of a MANTICORE.

Heavy iron sites like you describe are very common and a lot of users see this, even more so at European sites where habitation extends back thousands of years in some cases. Some users (more so in North America than Europe it seems) are having particular difficulty with iron. Certain types of iron, combined with low soil mineralisation like what you describe (and is quite common in North America) seem to make this the most difficult. (Interestingly, users in higher soil mineralisation seem to have much less difficulty.)

Iron targets often exhibit non-ferrous falsing when the coil is off to the side of the target, particularly when mixed with some ground noise (for example from weakly mineralised ground). With the MANTICORE, the signals are stronger, and so what sounded like a choppy audio response on the 800, can be a stronger, clearer 2 way response on the MANTICORE. However, we find that in almost every case, when the coil is over the center of the target, the response is ferrous.

You might say that the EQUINOX 800 choppy audio response is better in the case of iron falsing, and perhaps this is so for iron falsing. But iron falsing is very difficult to distinguish from co-mingled targets, and the EQUINOX 800 will also give you a choppy response on many co-mingled targets, and in many cases won’t be enough to stop you.

We can suggest a couple of things that may help. In the short term, on sites like this, I recommend using Pinpoint Mode to locate the centre of a target and quickly checking it again in detection mode with the coil centered on the target. A consistent ferrous response on the center of the target which turns to non-ferrous off to the side is a giveaway that you have iron falsing. A couple of seconds in Pinpoint mode is one of the best ways to distinguish between 2 targets, and one piece of falsing iron. Many experienced users don’t think they need to use Pinpoint, but it can give you more than just target location information.

You can also expect a software update in the near future that will provide a setting that helps you distinguish audio signals that have a good chance of being iron falsing. I believe you will find this update will significantly help you in the scenario you describe, and make detecting much easier.***

 

 

 

[TampaBayBrad]

I am a beach hunter with non-mineralized sand and not near the iron in the ground that you have. My problem child is aluminum. When I have a piece of non-ferrous aluminum next to another type metal which is also non-ferrous, what you are doing by crossing in all directions usually sniffs out the good target at a different location on the non-ferrous center line. Meaning I have two dots showing up on the line (with the aluminum dot being to the left usually under 12 or so positioning) and the ID #'s bouncing between the two on at least one direction sweep. I run prospecting audio, so that's different from your set up also. I run recovery 4 and sensitivity on dry sand at 21 in beach low conductor mode, again different from what you have yet we both have trash that we are trying to differentiate when close to a good target.

I think in your case of iron falsing, the official word from Minelab quoted above that fishersari posted is valuable info to know that may help in your testing/experimenting.

[Dug D]

Wow there is a lot here to read, I had similar experience especially with ATHC. 

I would avoid ATHC unless the site is reasonably clean. (almost every nail will create a false higher/high signal about 4 inches of the end of the nail)

One very easy thing I have done is, find the target with whatever sensitivity and then back down the sensitivity 3 or 4 or more levels and see if the good target remains while Xing it with the coil.  I have found the detector WILL in most case hit a coin harder than a nail. 

Pushing higher sensitivity where there are nails in a park has not netted me any more coins only more frustration. 

[UT Dave]

The note from ML posted above by @fishersari reminded me of something.  The live VID in pinpoint on the Manticore is pretty under rated in my opinion.  Especially with the M8, pinpoint mode is actually pretty awesome at sussing out collocated targets.  With the M8 you can get completely different VID's only a couple inches apart in pinpoint.

- Dave