Air test vrs. field test

[m bryan]

under normal conditions should the depth be about the same?

 

Amazon Forum Fav 👍

A History of Mining on the Kenai Peninsula, Alaska - Grab it through Amazon!

[Iron Patch]

Yes, pretty close. You'll read plenty of people say certain detectors do better in the ground than in an airtest, like my Explorer... but that's not really the case. I think a halo does make a detector like the target better, but don't think there's much of a difference in depth. (Seems like a contradiction but that's my experience) My detector will airtest a small silver coin about as deep as I've ever dug one, and am pretty sure it would be the same for all other targets too. In many cases the airtest can be better, and the ground killing some of the depth on certain units. Where real in the field experience counts is all the variables that are thrown in.

 

[U.K. Brian]

I've got machines that air test to 16 inches. You might get 10 inches in good ground and I've a few bad sites were the depth comes down to 2 inches.

The old "Testy" (Polish testing site I think) was interesting as it demonstrated that some of the flagship machines of the time (just pre the Explorer coming out) lost most depth between air and in ground tests. Didn't mean the most expensive detectors didn't still have an edge but perhaps not enough to justify the extra cost. XLT with stock 9.5 coil tested 30cm in air but only 21cm in ground. The far cheaper Quantum XT (9.5 coil) air tested 26 cm and 20cm in ground so almost the same performance as the XLT.

My own test with a Whites Classic III (9.5 coil) showed a 9 cm difference but swapping to an 8" coil the in-ground loss was only 4cm. I assume the extra size of the bigger coil pushed the detector beyond its ability to cope with the ground minerals. Minelab BBS/FBS have always been a little odd as they don't like air to much. With a Sovereign "Auto" will not test well in air as its trying to automatically adjust sensitivity to the ground conditions and there aren't any.

 

[luvsdux]

This is just my very untested, non-scientific opinion. If you could compare in truly neutral, non-mineralized soil, I think the difference would be little to none. However in real life field test the soil will vary sometimes considerably from location to location and under those conditions I'm sure the in ground depth will always be somewhat less to quite a bit less depending on all the variables. Just my two bits.
HH
luvsdux

 

[rockhound]

Whereas an air test has no variables whatsoever, in the ground, many variables come into play. Moisture, mineralization,and conductivity of the soil, will have a huge impact on depth. Iron or other magnetic materials effect the ground balance severly on most detectors, rendering some detectors almost useless. In a soil absent of mineralization and with the proper amount of moisture, it could be possible to attain the same depth as in an air test. Happy Hunting. rockhound

 

[George (MN)]

I seem to lose 40%-60% in my ground compared to air. The professional field testers seem to get coins at the full air test range even in rather mineralized ground with correct IDs most of the time. When I see they got a coin down 7" I tell myself that detector will do 4" in my soil. HH, George (MN)

 

[Iron Patch]

The professional field testers seem to get coins at the full air test range even in rather mineralized ground with correct IDs most of the time.

Professional = paid for their tests which = don't believe everything you read.

 

[Woodland Detectors]

The professional field testers seem to get coins at the full air test range even in rather mineralized ground with correct IDs most of the time.

I would like to meet a professional air tester someday.

Professional = paid for their tests which = don't believe everything you read.

 

[bigscoop]

Hu........interesting. I seem to get just the opposite results, "my machines hunt deeper in the field then during an air test" and with identical targets. Take a handful of coins and air test each one, then dig yourself a few holes of various depths and take turns burying the same coins one at a time and fill the holes back in over the coins. I've done this many times and my machines almost always read deeper then in an air test. My hunting partner and I have done this many times while comparing different machines, settings, and coils. Seems we always get deeper and better results in the field.

 

[Iron Patch]

Hu........interesting. I seem to get just the opposite results, "my machines hunt deeper in the field then during an air test" and with identical targets. Take a handful of coins and air test each one, then dig yourself a few holes of various depths and take turns burying the same coins one at a time and fill the holes back in over the coins. I've done this many times and my machines almost always read deeper then in an air test. My hunting partner and I have done this many times while comparing different machines, settings, and coils. Seems we always get deeper and better results in the field.

You must have some mineralized air.