Disc/Depth

[Architex]

As near as I can tell from other posts and from my own experience, if what you're after is just depth, the less disc the better, down to and including none at all. Is that always true or am I missing something.

 

[Jason in Enid]

That is true on all other discriminating VLF detectors, it is not true on FBS.

regular detectors show target's VDIs getting worse and worse as depth increases until it only sees it as iron, then nothing at all. This is why they say you "lose depth" as you increase disc.

I have never seen this happen with either the E-Trac or CTX I have owned. the FE side of the scale may increase a little but you always still have the same area of CO response. Once a conductive target is at the very threshold of detection depth you get a CO response with an iron "thunk" instantly after.

 

[sgoss66]

Ahh, yes, Jason. The Minelab "thunk!"

Steve

 

[Architex]

Snow on the ground right now with single digit temps. As soon as weather moderates I'll be listening for that thunk. Thanks for the replies, I obviously have things to learn.

 

[Jason in Enid]

Snow on the ground right now with single digit temps. As soon as weather moderates I'll be listening for that thunk. Thanks for the replies, I obviously have things to learn.

No need to wait, you can do it in your home. Just put it in a low manual sensitivity on your couch our some place and wave a coin past it as you slowly move it farther and farther back. Youll find the thunk.

 

[Architex]

Good Grief !!! How many times have I heard that thunk not realizing it meant something !!! Thank you. Anyone have any "pay attention" pills?

 

[Jason in Enid]

Good Grief !!! How many times have I heard that thunk not realizing it meant something !!! Thank you. Anyone have any "pay attention" pills?

remember, its not JUST the thunk, its the beep and thunk. if you go chasing thunks, you'll be digging a lot of iron. BTW-this isnt fool proof.

 

[Chris(SoCenWI)]

The deeper a target is in the ground the more likely the signal is to be influenced by soil mineralization or other closely located targets. If you swing over a deeper target you are more likely to see different target IDs on each swing. A shallow target will give a more consistent ID.

So.. If you have lots of discrimination, especially learned in tight discrimination, on the majority of the swings over a deep target you will get a null, not a signal, and will continue on your merry way. The shallow signals will come through more consistently, giving the perception that discrimination kills depth. In super clean ground, no junk, no mineralization you should get the same results. I've been detecting since I was 10 years old and have never found such a site.

Chris(SoCenWI)

 

[IDXMonster]

The deeper a target is in the ground the more likely the signal is to be influenced by soil mineralization or other closely located targets. If you swing over a deeper target you are more likely to see different target IDs on each swing. A shallow target will give a more consistent ID.

So.. If you have lots of discrimination, especially learned in tight discrimination, on the majority of the swings over a deep target you will get a null, not a signal, and will continue on your merry way. The shallow signals will come through more consistently, giving the perception that discrimination kills depth. In super clean ground, no junk, no mineralization you should get the same results. I've been detecting since I was 10 years old and have never found such a site.

Chris(SoCenWI)

Detecting since you were 10 years old?? You must be TIRED!

 

[sgoss66]

IDX -- LOL!

Yes, I agree with the posts here. Just simply RUNNING disc. on an FBS unit should not -- in and of itself -- affect depth. In other words, if you are running open screen, and then add some rejected area, you haven't "automatically" reduced depth capability of the machine. I'll say why I think so in a second, but first I want to say that I TOTALLY agree with Jason and Chris. Losing depth on FBS when running disc. would be a PERCEPTION thing. There is no doubt that target ID will often deteriorate with depth, possibly deteriorating to where it fluctuates OUT OF an accepted pixel, and INTO an discriminated one (depending upon the "tightness" of one's disc. pattern. Thus, with the target possibly fluctuating in and out of accepted and rejected areas, the result would be a "junkier" sounding target, and thus perhaps a "no-dig" decision on the part of the operator (especially if there is some inexperience there). And thus, a failure at times to dig deeper targets. But, like Chris and Jason said, that's not a "loss of depth" within the unit, due to running disc., it's a "loss of depth" due to "errors" made by the operator.

OK -- so the reason I don't think you ACTUALLY "lose depth" on FBS if running disc? It's because since there's not a true "all-metal" mode on FBS, and that suggests that the unit is already "running the raw signal through an ID/discrimination circuit" so to speak, in the first place. So even if you run an "open screen," the return signal has still already passed through that "circuit," which means that any "loss of depth" from the raw signal to the processed one would already have happened -- back when the raw signal passed through the circuit and was processed to obtain ID info. At that point, telling the already processed signal to "be quiet" (discriminated out), or "produce a tone" (accepted) should be irrelevant to depth.

There's no doubt that on some machines with a true, all-metal mode where a more "unprocessed" signal can be monitored by the operator if all-metal mode is selected, you can get "more depth" than you could in disc. mode -- by listening for subtle "threshold wavers" or whatever. And in these cases, "depth" would be "lost" when you switch into disc. mode -- because that "threshold waver" will usually not successfully be assigned an ID within the ID/disc. circuit, and thus is not given an audio tone -- and thus the overall effect is, you can hear "deeper" targets in all-metal mode than you can in "disc." mode. But again, since FBS does not operate in this way (no true all-metal mode, and all receive signals passed through ID/disc. processing, as far as I can tell), then the "rules" that are associated with machines that are deeper in "true all-metal mode" and "not as deep" in disc. mode, don't apply to FBS.

That's how I understand it; I'm pretty sure I'm not too far off base here.

Steve

Steve

 

[sube]

I agree what has been said so far . However pinpoint sizing is deeper than the disc mode 1 to 2 inches deeper I don't know how pinpoint sizing works tech wise but is deeper and still uses target trace as a disc mode in pinpoint so we still have disc in pinpoint .

Remember sensitivity #s do the same for target trace in disc mode as they do in pinpoint mode low #s not as good of trace high #s better trace .
It gets to the point where a target is to deep to get a trace even by jacking sensitivity #s to 30 then you will have to remove soil or try to size the target so it sounds the same and the length of the target is the same to tell if it has a chance of being a coin or not.

But when we get a shallow small target with no trace it's the same as a deep target with no trace one has to dig a shallow hole and see if it's small and shallow or deep not many other choices . Also speeding up you swing on the pinpointed target with disc mode well sometimes give a much better trace than swinging at a slower speed .

Chris is right about the ground we cover if it's got any mineralization or rust and whatnots it's going to give less depth, that said the more whatnots the less depth you will get. sube

 

[sgoss66]

Great stuff, sube.

I believe that I have noticed a bit more depth in pinpoint mode, as well, which is a "curve ball." If pinpoint had no ID info and no "target trace," I'd say "it's not running through the ID circuit, that's why it's deeper." BUT it obviously IS running through the ID circuit. So I'm not sure there...

Steve

 

[sube]

Well maybe it's only running through the target trace part of the id circuit and not the audio .There separate but run as one when iding what one does the other does the same . I guess we well never know but pinpoint is deeper than disc so sube

 

[Tony N (Michigan)]

The deeper a target is in the ground the more likely the signal is to be influenced by soil mineralization or other closely located targets. If you swing over a deeper target you are more likely to see different target IDs on each swing. A shallow target will give a more consistent ID.

So.. If you have lots of discrimination, especially learned in tight discrimination, on the majority of the swings over a deep target you will get a null, not a signal, and will continue on your merry way. The shallow signals will come through more consistently, giving the perception that discrimination kills depth. In super clean ground, no junk, no mineralization you should get the same results. I've been detecting since I was 10 years old and have never found such a site.

Chris(SoCenWI)

[size=large]Good thoughts Chris,
Man! You started detecting when you were 10? Did your dad get you started?[/size]

 

[Tony N (Michigan)]

The deeper a target is in the ground the more likely the signal is to be influenced by soil mineralization or other closely located targets. If you swing over a deeper target you are more likely to see different target IDs on each swing. A shallow target will give a more consistent ID.

So.. If you have lots of discrimination, especially learned in tight discrimination, on the majority of the swings over a deep target you will get a null, not a signal, and will continue on your merry way. The shallow signals will come through more consistently, giving the perception that discrimination kills depth. In super clean ground, no junk, no mineralization you should get the same results. I've been detecting since I was 10 years old and have never found such a site.

Chris(SoCenWI)

Detecting since you were 10 years old?? You must be TIRED!

[size=large]He's probably so tired he's re-tired.[/size]

 

[Jason in Enid]

Well maybe it's only running through the target trace part of the id circuit and not the audio .There separate but run as one when iding what one does the other does the same . I guess we well never know but pinpoint is deeper than disc so sube

I've noticed this as well. There have been some targets that are definitely on the verge of detection depth but they pinpoint loud and clear. I've never tried to use it as a hunt mode though. I think I'd go crazy, most of my sites are full of nails and I'd be glued to the screen constantly. It is something to consider for the spots where you just cant get any more keepers from.

 

[IDXMonster]

I wonder if “disc vs pinpoint” operation is deliberately set up this way so as to never have an issue pinpointing a target that has been found with disc? Just thinkin’...

 

[Jason in Enid]

The water hunters say the Excalibur is deeper in pinpoint than disc for that too. I know some of them hunt in pinpoint mode and use disc to check targets. They call it "reverse discrimination"

 

[sube]

I wonder if “disc vs pinpoint” operation is deliberately set up this way so as to never have an issue pinpointing a target that has been found with disc? Just thinkin’...

Maybe but if you turn off target trace you still are using disc in pinpoint mode if the target is still in range you will get a cursor where the target is suppose to land it won't have any red in it because it's to deep anyway so target trace isn't doing anything for you at fringe depth .

Now on the other hand when we go to pinpoint we don't have ( disc audio ) but we still have audio so maybe getting rid of disc audio and just getting audio is why we see a difference in depth. sube
Jason said
I've noticed this as well. There have been some targets that are definitely on the verge of detection depth but they pinpoint loud and clear. I've never tried to use it as a hunt mode though. I think I'd go crazy, most of my sites are full of nails and I'd be glued to the screen constantly. It is something to consider for the spots where you just cant get any more keepers from.

Jason even though your in pinpoint mode nails well double hit one way but I know what you mean lot's of signals .sube

 

[sgoss66]

The water hunters say the Excalibur is deeper in pinpoint than disc for that too. I know some of them hunt in pinpoint mode and use disc to check targets. They call it "reverse discrimination"

So THAT'S what is meant by those water hunters when they say "reverse discrimination?"

I had heard that term before, and what you say makes total sense; I'd just never put two and two together before.

It's a good day today! I learned something new!

Thanks, Jason!

Steve