Target Masking: How relevant is this 16 year old article to today's technology?

[TrpnBils]

The following article was published in Western & Eastern Treasures magazine in 2000:

Beneath The Mask

I encourage you to read it if you haven't already (it's been making its rounds on forums for years). It deals with target masking and outlines one project where the author "totally cleaned out" an area on a baseball diamond with one detector, verified a lack of targets with a second detector, and then proceeded to find over 1000 items in that same space with a PI detector that was intended to find excessively tiny targets that the other detectors missed. Beneath these tiny targets (fragments of staples, etc) he found coins that were masked along with other items larger than the things that were masking them.

He says, "And I think I could safely say that less than 20 percent of the coins in the schoolyards and parks have been recovered because of masking, silent masking and deep depths." That's encouraging if it's true, because all it takes is a little bit of new technology (which there has been a good bit of in the 16 years since this was written) or some change in soil or target position due to weather or other events to uncover something that's been missed for years.

My question is this: Considering the advancements brought by the 3030, which itself is a few years old by now, including target trace, multiple target ID, and FBS technology how relevant is this article in 2016? Can a standard staple still mask a coin from 4" away? How can we use the 3030 to our advantage and get ahead of the masking of targets?

 

[CZconnoisseur]

The article in my opinion is still 100% relevant...no matter what machine you are using. I've seen aluminum foil mask a 3" deep silver quarter - the machine I was using "blended" the two targets and made it sound like a pulltab. However, the area I was hunting was older, so almost everything got dug. As far as a staple masking a 4" deep coin...I think technology has overcome that problem in at least the higher end machines, since I've dug staple fragments with coins on more than one occasion, and the signal sounded very "coinlike"

Recently trojdor and I have been pushing our machines to the limit at some local spots, and both of us have been finding great targets at the edge of detection....almost every hunt! I can't tell you how many times I've pulled Indian cents from holes that first gave up multiple nails, or finding a deep rusty bolt only to rescan the hole after the bolt is removed to pull a deep, 100+ yr-old coin. I remember one target a few months ago was a fairly large irony signal, and no indication of anyting non-ferrous - which was a rusty set of steel keys. Just a little offset of the keys I got a confident non-ferrous hit and pulled a 6" deep Wheat cent that was previously masked by the keys....

Many times we comment on how many times we've thought a place has been detected by thousands of detectorists - how many times we've speculated on iffy targets that, at some point in the past, a detectorist may have passed over the iffy hit, looking for lower-hanging fruit. But then when we come along, and dig almost exclusively those iffy hits to reveal a coin co-located with foil or iron. Between the two of us, we have a CTX 3030 and a 9" Deus - and both of these machines will hit those iffy targets rather well, and we compare those questionable hits almost every time.

Don't get me wrong - the majority of what we dig are folded beavertails, deep pieces of flat foil, nails, etc...but every now and then either one of us will get a desperate hit that *could* be a coin - and get rewarded usually with a keeper.

 

[sube]

I agree with CZconnoisseur on small iron and small pieces of foil as long as the signal under the foil or small iron is stronger than the item masking it these well report may not be perfect #s but they will tell you they are there .

Now pull-tabs bottle caps and larger foil will make the coin go silent . if your coins are 6 inches or less you well find more of what's there because the signal of the coins well be strong enough to give you a clue of something under the masking signal .The deeper the coins you have in your ground the more masking is taking place because the return signal is weaker than the masking signal .

I love that article I have read it when it came out and hunt accordingly to it . the ctx and deus both are better detectors than what was used back then but masking still happens more than you know the ctx will see a coin under a nail by 1 inch to 1 1/2 inch this is new ground that has not been searched before so it's getting better .Targets that are below foil tabs and other items well blend the coin signal as one throwing the vid off such as pull-tab dime coming in at 12.35 nickel tab well be 12.17 depending what type of tab is with it .

20 percent no not where the coins are 6 inches or less coins 8 inches and deeper I would agree a 100 percent just the way it is right now .Ctx well find many coins older detectors will not these are masked coins but silent masking is still going on with deeper coins. Coins that are shallow 6 inches or less well still be masked by pull-tabs bottle caps and what ever . sube

 

[trojdor]

I think CZconnoisseur and sube hit it on the head...it's still very relevant today.

Most people, including some Detectorists, vastly underestimate the raw quantity of 'stuff' in the ground...and how that affects the detector operation.
I'm always entertained by those new to the sport, for whom the quantity of junk they find is unbelievable to them.
I know when I first started, I was flabbergasted by how much metal was in the ground.

In the very early days of discrimination, we wanted the detector to ONLY show the POSITIVELY GOOD targets. Digging even one pull tab was often considered unacceptable.
Times change. Now, for the most part, we're looking to clean up the ones that got left behind.

Some advances in technology have certainly been made to 'unmask' co-located coin/junk targets, but it comes with the price of digging more...and keeping less.
The modern detectors have a lot more tools, options, and processing power...but it's still up to the operator to use them to their fullest...on those 'iffy signals, and make the final 'dig' decisions.

One way to be better at this, is to experiment with junk/coin co-located targets in the ground. Creep in from different angle to hear the different responses.
Use the PP Trace and target trace to help you get a mental picture of what's in the ground.
(Sube has at least one video about 'sneaking up' on a coin next to iron, that is a must see.)

Another way is to stop looking for that 'perfect' signal when hunting, and try to sniff out some of those deeper, 'iffy' targets.
See if you can guess what it might be, before you dig.

In other words, to find more keepers...look more for reasons TO dig, as opposed to looking for reasons NOT to dig.

HH,
mike

 

[IDXMonster]

Excellent Mike,very well put!

 

[TrpnBils]

Another way is to stop looking for that 'perfect' signal when hunting, and try to sniff out some of those deeper, 'iffy' targets.
See if you can guess what it might be, before you dig.

In other words, to find more keepers...look more for reasons TO dig, as opposed to looking for reasons NOT to dig.

HH,
mike

As you and I have discussed lately, this is absolutely my downfall right now. I feel like there are so many iffy signals and 99% of the ones I dig are just junk so I, without intending to, ignore just about everything but the best sounding ones and it's irritating as hell. I know I'm passing stuff up, but I can't bring myself to stop and dig when I'm positive it's going to be trash (based on experience).

 

[Johnnyanglo]

"I feel like there are so many iffy signals and 99% of the ones I dig are just junk ..."

My experience with the CTX (and the E-Trac) in iron strewn ground, if the Co-value is in a good region, though it may be jumpy but is jumpy in the good region, then dig. The Fe-value can dive into the high Fe-values with each sweep, but that should not be the deciding factor. You can think of the Co-value as the 'character' of the non-ferrous target, if the character holds close within a region then there is a high reliability that the target is exactly that, non-ferrous. The Fe-value simply indicates the amount of iron (nails) or iron minerals present but independently it cannot confirm the non-ferrous character of a target. Rather it is a clue to the ferrous nature of the ground matrix, which isn't the kind of info you need to decide whether to dig or not.

In other words, a high Fe-values combined with a Co-value that jumps about with each sweep is an iron target, but a high Fe-value combined with a somewhat stable Co-value is a non-ferrous target in a sea of iron. Don't expect the Co-value on a deep coin to be accurate, it is likely to creep up the Co-scale toward higher values and in some cases to lower values - the important detail is the stability not the absolute value.

Else, if you demand the CTX provide a stable Fe-Co pairing, then you are limited to shallow targets (< 6" deep) in moderate mineralized/iron ground. That's fine, but getting the deeper non-ferrous using that rational will cause you to pass the high Fe target by; the Fe value isn't the discriminator and shouldn't be relied upon. And, sure large iron will mimic a good target by projecting a more stable Co-value, nothing is foolproof. But if you know that old coins are likely, and they are expected to be deep, then you can't use a stable Fe-Co TID as your criteria to dig (unless you're in low mineralized soils such as coral sands). In the presence of iron you have to change the tactic you use to evaluate the signal.

Johnnyanglo

 

[TrpnBils]

In other words, a high Fe-values combined with a Co-value that jumps about with each sweep is an iron target, but a high Fe-value combined with a somewhat stable Co-value is a non-ferrous target in a sea of iron. Don't expect the Co-value on a deep coin to be accurate, it is likely to creep up the Co-scale toward higher values and in some cases to lower values - the important detail is the stability not the absolute value.

Else, if you demand the CTX provide a stable Fe-Co pairing, then you are limited to shallow targets (< 6" deep) in moderate mineralized/iron ground. That's fine, but getting the deeper non-ferrous using that rational will cause you to pass the high Fe target by; the Fe value isn't the discriminator and shouldn't be relied upon. And, sure large iron will mimic a good target by projecting a more stable Co-value, nothing is foolproof. But if you know that old coins are likely, and they are expected to be deep, then you can't use a stable Fe-Co TID as your criteria to dig (unless you're in low mineralized soils such as coral sands). In the presence of iron you have to change the tactic you use to evaluate the signal.

Johnnyanglo

Around here I've noticed that CO values tend to drop in deeper stuff. I dug two Mercury dimes two weeks ago at 12-41 and 12-42 (although they were pretty worn too, so that might be a factor).

Having used the Etrac I'm comfortable with the idea that the Fe number will climb while the Co number stays relatively stable. Let me describe a situation that I saw the other night and see what you think. My back yard is the upper tier of a 1950s drive-in theater. I don't hunt the yard much because I haven't found a coin in it in two years at least. Before that, I found probably a dozen wheats, a silver Roosevelt, and some modern clad. I assume there's probably other stuff there, but the signals (even iron) are few and far between now. Thoughts go to deep stuff.... or something that's masked. I was out the other night with the stock coil on and manual sensitivity set at 22 (recommended 16). In combined ferrous-coin mode I would get a high tone that was repeatable probably every 2-3 sweeps at different angles, It wasn't a fully repeatable signal, but it was better sounding than anything else I was getting. The cursor was moving around to about two or three different spots in the 40s conductive. At the same time though I was getting a pattern showing up in the iron areas at the bottom of the screen (wide open) that was exactly the same as the pattern I was seeing up above.

When I'd try to pinpoint, all I would get would be a vague gray area that didn't really produce any colors so it was hard to figure out exactly where it was. It was almost dark, so I didn't really get into it, but I'm probably going to go out and try to pinpoint it just through audio on the sweeps and see what comes up.

My questions to you or anybody else in the know here:

1. If the trace pattern showing up in the iron area matches the shape of the pattern showing up in the conductive area, does that indicate anything in terms of whether it's just a false off of the iron versus an actual second target?
2. If I get colors on target trace during a regular sweep but not during pinpoint, does that indicate anything in terms of whether or not it's worth pursuing?

 

[Champ Ferguson]

....When I'd try to pinpoint, all I would get would be a vague gray area that didn't really produce any colors so it was hard to figure out exactly where it was. It was almost dark, so I didn't really get into it, but I'm probably going to go out and try to pinpoint it just through audio on the sweeps and see what comes up....

If you can flip over to a program running 50Conductive, it might give you more info on what the conductive value is.

 

[sube]

Quote 1. If the trace pattern showing up in the iron area matches the shape of the pattern showing up in the conductive area, does that indicate anything in terms of whether it's just a false off of the iron versus an actual second target?
2. If I get colors on target trace during a regular sweep but not during pinpoint, does that indicate anything in terms of whether or not it's worth pursuing?

? 1 generally if the target is mimicking the cursor on the bottom the same as the 12 line these targets or target is as one coin tight with the iron or just iron if you can not separate the targets then they are basically just one target . being coin with iron or plain old iron .
These targets well go back and forth on the 12 line same as the iron box in the right hand corner with these targets I would look at the co #s for stability . Then build my trace I also have my 31 to 35 line disc out on screen 1 just for this to see if it's a real iron cursor in the bottom right corner it well be confirmed with a diamond and if the iron signal (audio ) goes away it's iron however if I still get a higher signal response than iron I'm digging .

?2 Remember your in motion mode tends to false more than pinpoint mode pinpoint mode is non motion much more stable than motion mode does not false like motion mode .
So if you can not build target in non motion mode I would say false . But don't en gauge the pinpoint mode directly over the target this will detune to this piece of ground making trace weaker engage a foot above the ground and then come in from the side and build the target . if you push the pinpoint button again over the target it will detune more and make the trace even weaker in pinpoint sizing with trace .

One tip if your having a hard time separating targets from one another use pinpoint sizing over the target as you detune by pushing the button several times you well make the detector weaker and weaker there by not using full power and making the target a blended signal
which well look like only one target there . Easier to separate with less power . sube

 

[alex74]

FBS Technology was already available in 2000 (Explorer)