"This myth is Busted"

[ivconic]

"...This myth is Busted
Can machines that don't air test well, go deeper in the soil ?
No absolute Crap !! this is scientifically impossible if a machine air tests badly it will detect badly in the soil despite what you read on metal detecting forums and some manufacturers literature.
However some machines that air test better can loose a higher percentage of depth in the soil around 30% depending on what type of search coil is used.
If you suspect these results are wrong, please go out there and do the buried coins test for yourself.
I think you will be amazed!!!!..."

This is quote taken from here:
http://www.garysdetecting.co.uk/hoard_test.htm

Fancy! I tell ya!
Almost to agree with.
And also sounds pretty sane and logical too.
And yes; it is true... BUT only in case we are talking about freshly buried targets in soil.
In such case yes it is true; machine will perform worse on target in soil than in air.
But what if target is lying there in soil for 2000 years?
We already talked about that several times in the past.
What about so called "hallo" effect?
Is it "hallo" or "echo" or whatever else; not really important, important is that it is a fact that it exists and it helps significantly in detection.
Well... listen... it is really not my fault because some people are so handicapped by not having the sites and opportunities to search for real Archeology.
They are handicapped because they can't search for 2000 years old targets in soil.
While at the same time lot of us can. Simply it is a matter of fact where are you residing and do you have or not such sites.
Nobody's fault actually. Just objective circumstances.
And from the perspective of someone who can search on such sites; i claim that most of the existing models (if not all) are able to perform better on such targets than in air.
Again... this not supposed to be taken as ultimate case, 100%.
It also depends on climatic conditions and period of a year and day.
But in most of the cases it will be the rule actually.
Now... you may ask what this is got to do with anything... what's the point?
Well... point is very simple and clear.
Artificially prepared testing conditions are not reflecting the truth and reality on real sites.
I am buying detectors to search for real and precious targets, the real Archeology.
I am not wasting my money on toys to play with on testing beds.
For that purpose i am already having Minelab simulator, splendid little md game!
What interests me mostly at metal detector is simple fact; how it will perform in reality, on real sites that i am having here at home.
I am not interested at all of how it "should" or would perform on some artificially made testing bed somewhere in some backyard in UK.
Simple as that.
That's the horrible "the other way around" and "thesis switching" which some people are trying to establish as ultimate (and only) truth.
Well... you can fool out some novice and beginner; but you can't fool me.
Besides, i am not writing all this for the sake of my own awareness. I don't need that.
I am writing this only for the sake of global md community awareness, especially to help novices and beginners here.
Sometimes i really feel like Don Quixote, by putting enormous efforts and all my nerves to stand for the real truth.

[ivconic]

No, "this myth" is not busted at all.
With such nonsensical articles is entered only further confusion in the whole story.
And possible eventual readers are mislead even further to bite that "truth".
MD problematic is pretty serious "business", needs much more than that.
Every experienced detectorist knows that.

[ivconic]

I am having so many examples during my detectorist "career" to prove my standing point.
I mentioned only few in my writings so far on forum.
When i come out and mention such case; i am than attacked by some self-proclaimed experts that i am an liar.
The other day i witnessed this nice find:


It was detected on certain depth in soil and just minute after it was detected barely at 1/2 of that depth distance in air.
How come?
It is the coin 2100 years old. It lied there in soil for 2100 years. Can you digest that? (you backyard prospectors)
It is P. Servilius M.f. Rullus. 100 BC. AR Denarius.
Nobody disturbed it for 2100 years.
That's somewhat different situation than simple fresh coin buried 2 days ago in own backyard, don't you agree?

[ivconic]

"...If you suspect these results are wrong, please go out there and do the buried coins test for yourself..."

This is the top of malicious hypocrisy, to say something like this.
Of course anyone can go out there, bury a coin and see the "truth", there is no question about that at all.
But that's not the point. That is not reflecting the reality from REAL sites and REAL conditions.
100% of us here can go outdoor and bury a coin like that; but only 20% of us here are having opportunity to visit sites that are having 2000 years old targets.
And that's on what "the experts" are mostly counting on.
Statistic is on their side. Statistic and "science" will hold their truth!
Of course!

[Nupi]

......................................
It is the coin 2100 years old. It lied there in soil for 2100 years. .................................................. .....

Why are you so sure that the coin already lied there in soil for 2100 years?

If you mention such an important theme here on Geotech I expect at least you make all the possibilities discussed.

It is also possible that he lied only 15 years and not 2100 years in the soil. Maybe 15 years ago come the coin into the soil just because a coin collector has dropped out of his pocket!

But seriously,
It may also be possible that the detector is triggered by another object (even iron) that lies deeper or near the coin. Also, moisture or spots with mineralization also be possible that the detector is triggered.
In other words, when these examples had not occurred maybe the detector did not detect the coin. Also this belongs to the possibilities. Thanks!!

No, "this myth" is not busted at all.

[Skippy]

That article on Gary site has been changed over time. It used to mention the 'sixpence at 10 inches' test more, but I recall that just about every machine failed to detect it, and it was considered a test failure. And originally, the 'myth is busted' statement was attributed to someone....gotta say I thought it was Georgi of Nexus detectors. I'll try and find out more...

[ivconic]

Why are you so sure that the coin already lied there in soil for 2100 years?

If you mention such an important theme here on Geotech I expect at least you make all the possibilities discussed.
It is also possible that he lied only 15 years and not 2100 years in the soil. Maybe 15 years ago come the coin into the soil just because a coin collector has dropped out of his pocket!
But seriously, It may also be possible that the detector is triggered by another object (even iron) that lies deeper or near the coin. Also, moisture or spots with mineralization also be possible that the detector is triggered.
In other words, when these examples had not occurred maybe the detector did not detect the coin. Also this belongs to the possibilities. Thanks!!
No, "this myth" is not busted at all.

Be serious!
I am not amateur nor novice to miss such simple things and to make false impressions.
It is the old site, dating exactly from that period. Coin was there for all that time. So as other targets we (my crew and me) collected that day.
I am serious detectorist enough to make sure and be certain about such things.
I have very strong rule to check the hole carefully after i take out the target. Also i know the difference in target signals against other possible signals.
But that's nothing so far to serve as any argument. You haven't payed attention on this little detail (sort of a trap, deliberately made):
"...It was detected on certain depth in soil and just minute after it was detected barely at 1/2 of that depth distance in air..."
I was precise about avoiding to mention exact depth.
And you fallen in that trap! Not you my friend!
Actually coin was very shallow! 10cm depth at most!
And once it is taken out of soil and held in hand for several seconds (it gets dry); same coin was barely detected at 5-6cm in air!
How come? Because it is "bad" silver, pretty awkward alloy. Very hard target. Locally called a "bilon" material. As you can see on photos.
So there is no room for any doubts there. We also had 20-30 more finds that day. But that one was most interesting as example.
Whenever i am trying to make a statement and prove something; i pick very precise examples. I never deal with random and approximate semi facts or semi truths.
This is too important subject to be approximative in such claims.
Like i said, this is just most recent example. I had similar cases so many times so far. There is not even slightest doubts in my mind about these facts.

[ivconic]

That article on Gary site has been changed over time. It used to mention the 'sixpence at 10 inches' test more, but I recall that just about every machine failed to detect it, and it was considered a test failure. And originally, the 'myth is busted' statement was attributed to someone....gotta say I thought it was Georgi of Nexus detectors. I'll try and find out more...

I am not very informed and sure if that Gary guy is the same one who made video in his backyard with hoard of coins at ~60cm depth, testing Deus with smaller and larger coils on those?
Really not sure, i never really remember the names of people who are out of my focus.
But i saw that video in the past. And than me and my crew made similar setup on our testing field. And results were pretty much the same.
Deus with smaller coil is detecting a hoard but only with iron tone. With larger coil 34x28 it is producing nice tone, correct one.
And there is nothing to disagree with in that video. Things are pretty clear; Deus is "lying son of a butch" too... in given conditions, of course. Just as any other model too.
But that's not the point of this topic.
We are not really interested to go out and dig freshly buried coins, are we?
We are interested to go out and dig ancient precious artifacts. That's what's only count in this "business".
Everything else is empty story.
Now... you can't test detectors on testing beds with freshly buried targets, than pull some conclusions from that, than make a claims and act as you are holder of only,universal and ultimate truth.
And at the same time call other people a liars, ignorants and irrelevant ones.
Because such experiences from such testing beds are just small piece of one big truth. Just a fragment. Proving so few things.
...
Ok, let me put it this way; why the hell they bothered in Compass to make "Depth Doubler"?
Why the hell they bothered? Is it a crackpot design? Crackpot idea?
Or maybe is it based on some real and truthful experiences from the real sites?
"Depth Doubler" supposed to help in depths at detectors. How? By "making artificial hallo effect", simple as that.
But since original natural "hallo" effect is very unpredictable phenomena; it is very hard to catch it and put it in exact scientific frame.
That's why also "Depth Doubler" is working good at some people and bad at others. Because it is only single "variable" in very complex formula with lot of other variables.
Natural genuine "hallo" effect is very complexly conditioned phenomena. And it is present and visible only on genuine ancient old sites.
Not in testing beds. Sorry.
That's why such testings are pretty far from reflecting any reality at genuine archaeological sites.
Results gained at such testing beds are very unreal and usually serves for most dirtiest interests, intentions and agendas.
In 110% of cases.
...
Unfortunately this is all what i was able to collect about "Depth Doubler"...

[ivconic]

Dave Johnson offered his point of view on this phenomena.
Lot of true elements in his article:

[ivconic]

The only thing Dave misses here is because of objective circumstances and fact that he is living in USA, not having direct experiences with conditions we are having here.
Targets which are dating back than from B.C. through ancient Rome period, than through Byzantine period and than medieval period are lying there in soil for indeed long time.
Usually mixed with all the "compounds" together that Dave named.
And that's why hallo effect is more present and easy visible here.
Bronze and copper coins may also have iron traces and impurities on their surface, due various reasons. Either it was made from bad mixture, alloy, either it adopted it from near iron object in soil.
When we talk about ancient Roman hammered coins, there are generally two groups of such coins. The "republican" minted and the "colonial" minted.
The "republican" minted from higher quality alloys, crafted and minted under the very strict rules by the state and emperor. Those were in circulation only at large centers at the time.
The "colonial" minted were from lower quality alloys, were in circulation between simple and ordinary people in colonized areas.
It is not impossible to find "colonial" piece with very high percentage of "bad" materials and higher percentage of impurities in it's alloy.
In shorter; there is not high level of uniformity between such targets, that's why is so hard to establish any kind of rule.
Next aspect is the place were such targets are discovered; the urban areas at the time. Such targets usually lie in the blended soil with the remnants of buildings and organic waste.
In shorter; lot of "chemistry" is involved at such places and area.
And that's what's missing at western experiences to fulfill the picture on "hallo" effect.
...
I would return now to a "Garrett case" which is pretty immense and known among local detectorists. This will also indicate the differences in understanding of things.
What i will say here is applying only on Garrett older series, like GTI and similar. I can't say nothing on newer models simply because i don't have direct experiences with those.
We all here do agree that those are splendid machines. Very powerful and very accurate. High quality made, reliable and very desirable to have.
But! GTI2500 for example behaves pretty deaf on above mentioned kinds of targets. Smaller "rusty" coins made from mixed and bad alloys.
I would say that GTI is having too "stiff" and restrictive filters for such targets. In AM mode there is no problem at all though.
Why the Garrett engineers made it that way?
It becomes obvious that they relied on the experience gained in their local conditions and lacking the experiences which i am talking about here.
So obvious.
Similar story with most of the White's models too. Except few exceptions.
But probably the worst case is with otherwise indeed well made Spectra.
And why the Fisher 1265/66 is behaving much better on such targets?
...
Those are collected experiences and knowledges which pointed small independent md manufactures in region to make detectors more suitable for local conditions.
There is no wonder why there are so much claims that some simpler md model performs better than some top model from branded manufacturer.
I guess Bulgarian Golden Mask is most illustrative and most significant example of machine perfectly suited for local regional conditions.

[ivconic]

And now the "finale"!
Knowing all that, all what i mentioned here on this topic; one will have clearer picture and more understanding for my standing point that it is huge nonsense to compare apples and pears and pull any sane conclusion from experiences gained on artificially prepared testing beds.
Especially if all those testings and demonstrations are performed on "fresh" targets, buried just "the other day" there.
That simply not do.
Not honest. Not fair. Not accurate.
It shows pretty twisted reality.
It has nothing to do with real life searching and real life situation on such sites.
Majority of those testings are done only to emphasize some md model, glorify it and put all the competition in inferior position.
Conditions on such testing beds are very carefully prepared and chosen to suit favored model.
No, "this myth is NOT busted".

[Nexus]

That article on Gary site has been changed over time. It used to mention the 'sixpence at 10 inches' test more, but I recall that just about every machine failed to detect it, and it was considered a test failure. And originally, the 'myth is busted' statement was attributed to someone....gotta say I thought it was Georgi of Nexus detectors. I'll try and find out more...

You are correct. This article in Gary's web site was at some point attributed to me, because I have buried the 1 kg of British coins in Gary's garden my self and I also have explained to Gary in detail what the whole story with super depth claims is about.
It is the same hoard that Gary used to claim that the Deus can get it, but that was before he removed the concrete pole out of the ground that was only 10-15 cm away from the hoard position.
Gary have at least two Nexus detectors in his storage and he knows very well that the silver six pence at 25 cm is no challenge for Nexus at all. But then he is working for XP now and I don't think he would talk much about Nexus depth performance anymore.

Finding six pence at 25 cm is very easy once folks learn how to use their detectors in true all metal mode.

I have also buries 1 kg of small Roman coins at 60 cm. in Mike Longfield's garden in Coventry. No one after 10 years have managed to find them by now. Not with Deus or CTX or any other detector.

[steaua581]

Hi Ivica,

I guess now this makes me dig whole plugs out and bring them home for testing ..lol I have watched many videos on youtube especially Russian (Klad)- I believe meaning treasure in in Russian, i must say i observe something interesting there and that is the x-terra 705, man bloody hell this detector took lots of clay pots out of the ground. I saw air tests with the x-terra but they are not impressive. There are 2 possibilities either the detector was cheap and everyone bought it so obviously found accidentally all these treasures or is the Hallo effect at play and the detector performs well in that regards.
https://www.youtube.com/watch?v=2RwFNA3XJSQ
Question is why x-terra 705 ? and not other detectors...

[ivconic]

Hi Ivica,

I guess now this makes me dig whole plugs out and bring them home for testing ..lol I have watched many videos on youtube especially Russian (Klad)- I believe meaning treasure in in Russian, i must say i observe something interesting there and that is the x-terra 705, man bloody hell this detector took lots of clay pots out of the ground. I saw air tests with the x-terra but they are not impressive. There are 2 possibilities either the detector was cheap and everyone bought it so obviously found accidentally all these treasures or is the Hallo effect at play and the detector performs well in that regards.
https://www.youtube.com/watch?v=2RwFNA3XJSQ
Question is why x-terra 705 ? and not other detectors...

That's excellent question!
Puts the light on another "factor" in this story.
As i said previously:
"... Because it is only single "variable" in very complex formula with lot of other variables..."
Yes, exact brand and model could also be the important "variable" in such "formula".
There are several md features on the line to be taken and included in to such "mathematics";
- Working frequency,
- Type of coil (DD, widescan, "Omega"...)
- Processing filters included in such desing, directly defining it's genuine purpose; relic hunter, coin shooter, beachcomber...
On some soils and some targets X-Terra will behave like that.
On some other soils and some other targets some other model will behave like that and X-Terra won't.
Story is very complex. Again i will repeat:
"...Natural genuine "hallo" effect is very complexly conditioned phenomena..."
And that's also another very strong argument to support my standing point that i exposed here.
You simply can't rely on the results gained on testing beds.
Such results are not reflecting the reality from the real situations.
Sometimes those are too far away from reality.

[ivconic]

http://www.njminerals.org/metaldetec...aloeffect.html

Excellent elaboration! Must read!

"...VIII. About That Detector
So.... don't fret about your brand-new detector. It wasn't designed to detect coins that you buried five minutes ago beneath six inches of soil.
In fact, if your soil is highly mineralized or has teensy bits of metal junk in it, this "soil air-test" can fail with just two or three inches of soil..."