HALO,,,Yes or No,,

In a discussion on another forum, some don't beleve in Halo's ,,,Below is a Copy & Paste from one poster....What do you think ???





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This is a really good discussion. I too used to believe in "halo" affect on all targets, but over the years that belief seemed to fade away. One of the main reasons is really deep targets. Quit often you get a really deep signal, only create a hole 10" deep and then you loose the signal. In this example, the target is still there, 2" deeper, still in matrix and "unidsturbed" dirt, but now your machine looses the signal. Why? Because now you have 10" of "air" over the target and the magnetic field reacts differently.

Granted, iron will leach heavily AND create a halo, but I no longer believe the other metals do to any degree that we could measure. After talking with Canewrap several weeks ago, I have been thinking about his belief and it really makes sense. Dave Johnson, Fisher engineer, also claims there is no such thing as "halo".

Great discussion you guys, thanks

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Sure there are "Halos"....but halos occur mostly with iron targets..or targets in highly corrosive soils. Still...I think generally speaking...halos dont contribute much to target "detectablity" in the average detectorists experience. The "Halo" effect that most experience is mostly a simple disturbance of the soil...which affects the electromagnetic "footprint" of the target as seen by the coil. Virtually everyone I've spoken to that has a better understanding of detector mechanics than I do.....says the same thing. Halos are largely a myth (when it comes to the things we commonly dig)..and do not have much bearing on day to day detecting!!! Streak!

I was testing the Halo theory once after finding silver dime at 5 inches w/ a great signal and then re digging it in another hole at 5 inches several feet away where i did not receive any other signal before burying it...I was using at the time a whites eagle spectrum...and I used the same program that I set for both coins...

The original signal was noticeably "stronger" and I believe kind of noticeably "clearer" then the pre-dug signal...not static-like as you mentioned above.

It could have been a fluke though...You never know what could cause something to signal the way it did...electrical currents closer, matrix change several feet away, the positioning of the coil, an 1/8 inch difference in the coil sweep to the ground, coil direction,...crap, dog urine soaking near the coin for all we know...I am kidding about the "pee", but even the sweeps angle of the coil might have been a degree or two different then the original coins sweep...

I guess it's fun to figure these things out, I myself love a good cryptogram...it's the detective in all of us...But unless you are ready to spend millions of dollars on equipment, work w/ a team of experts around the clock ...eating, sleeping and discussing nothing but the experiment, you are wasting your time wondering...Either dig it all, or be choosy...I guess it's fun to ponder, but my point is, once again, I don't really think it makes a diff, because even if there truly was a difference, some other "happening" could just level out the playing field.

HH

-mike



Edited 1 time(s). Last edit at 08/01/2008 01:19AM by PanMan.

Yes, Big misconception about halo's. The only thing a halo does...... is verify that the highly 'oxidizable' object is "electrically connected" to the soil better. How the target 'conducts' in the VERY near soil surrounding the object. And even with that......... it virtually makes nearly no detectable difference.

Mike, , , Sounds like you incurred some 'silent masking' in the re-bury of your silver dime.

Tom

Copper coins do leach into the ground, ever notice the green spot around an indian head penny or once found a 2 cent piece that was wet and actually bubbling...Have no specific proof if this does let you detect it deeper but do know a silver coin creates little or no halo...I realize in older yards wheaties outnumber the silver dimes but wheaties usually are detected deeper which to me says halo's exist on copper coins and do let you detect one deeper..

I have dug targets in the fall and winter when the ground is moist and they could be deep or just a few inches deep and when I pull out the silver or sometimes clad I can go over the hole with my coil and still get a tone. Then it starts to fade....Halo? I think it could be an effect from the target and the dirt maytrix and the moist ground? Kind of like when iron bleeds. Dirt has such an effect on coins. And then you throw in minerals from water, the sun warming the ground, you have an oven under your feet baking your targets or warming them.

I find the ground changes as the sun changes. So you have to have the skill to be able to read the ground and ajust your detector. I ground bal a lot sometimes in the gold country it is hard to find good ground to ground bal or fast grab so I am always looking for a sliver of clean ground and when I find it I really do a good fast grab and keep it that way till my detector starts to act up and on the F75 you have to be ahead of the dirt maytrix.

LowBoy

TAKE A LITTLE TIME KICKBACK AND WATCH SOME OF MY DETECTING VIDEO'S BELOW ON YouTube

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If you don’t dig it, then how are you going to know what you’re missing!
How can you have your pudding if you don’t eat your meat!

Dan,

A wheat penny has over 20% greater mass..... over a silver dime; hence, it's greater detection depth capabilities.