Findmall.com
 
 






Metal Detecting Forum


Welcome! Log In Register
Re: Got to be a reason. Fish finder vs metal detector
Posted by: Tom_in_CA
Date: September 01, 2017 09:57AM
Quote
bootyhoundpa
Ground penetrating rader might give you a little extra depth,lol.

For GPR, the trouble is, and always will be: Pixel size. The smallest the pixel resolution is, is about 1" across squares. Thus anything that md'rs look for (rings, tabs, coins, nails, foil wads, etc...) are all ........ doh .... one pixel. And as far as their depth, I believe you can accomplish the same depth on larger sized targets with most 2 box machines.

And d/t the inhospitable ground through which it must see through (solid terra firma) I don't think we're going to see the pixel size or depth improve. And even if the pixel sizes came down to a fraction of what they are now (1/10" inch, let's say), I bet it would still be useless for the average md'r. You are simply NOT going to see magical ring or coin shapes (as if you were viewing a TV, or fish on a sonar where you can tell the difference between species of fish even).

The reason is: Everything would still be nothing but a "mess of blotchy pixels". Here's an example of what I mean: Consider a horseshoe. That has a distinct and large (7" x 5") shape, right ? And there's no mistaking the tell-tale "shape" of a horseshoe, right ? But even at 1" pixels, guess what you see ? Nothing but a mess of blotchy pixels. Not a "horseshoe shape". So to apply this logic to ... let's say ... a pulltab with a beaver tail versus a round coin (or ring) with no "tail": Even at 1/10" pixel size, you STILL only see a "mess of blotchy pixels". Not a magical tab versus ring shape. And also: The moment you add the SLIGHTEST tilt, you can kiss shape-showing goodbye.

Re: Got to be a reason. Fish finder vs metal detector
Posted by: Dancer
Date: September 01, 2017 11:26AM
Quote
Tom_in_CA
Quote
bootyhoundpa
Ground penetrating rader might give you a little extra depth,lol.

For GPR, the trouble is, and always will be: Pixel size. The smallest the pixel resolution is, is about 1" across squares. Thus anything that md'rs look for (rings, tabs, coins, nails, foil wads, etc...) are all ........ doh .... one pixel. And as far as their depth, I believe you can accomplish the same depth on larger sized targets with most 2 box machines.

And d/t the inhospitable ground through which it must see through (solid terra firma) I don't think we're going to see the pixel size or depth improve. And even if the pixel sizes came down to a fraction of what they are now (1/10" inch, let's say), I bet it would still be useless for the average md'r. You are simply NOT going to see magical ring or coin shapes (as if you were viewing a TV, or fish on a sonar where you can tell the difference between species of fish even).

The reason is: Everything would still be nothing but a "mess of blotchy pixels". Here's an example of what I mean: Consider a horseshoe. That has a distinct and large (7" x 5") shape, right ? And there's no mistaking the tell-tale "shape" of a horseshoe, right ? But even at 1" pixels, guess what you see ? Nothing but a mess of blotchy pixels. Not a "horseshoe shape". So to apply this logic to ... let's say ... a pulltab with a beaver tail versus a round coin (or ring) with no "tail": Even at 1/10" pixel size, you STILL only see a "mess of blotchy pixels". Not a magical tab versus ring shape. And also: The moment you add the SLIGHTEST tilt, you can kiss shape-showing goodbye.

Tom, I believe everything you said. But
Remember when the Earth was flat, can't put a man on the moon, team going from last to first, horseless carriages, all these were impossible too. The pixels will shrink, we just might be around to see it. Lol

Re: Got to be a reason. Fish finder vs metal detector
Posted by: Tom_in_CA
Date: September 01, 2017 12:23PM
Quote
Dancer
..... Tom, I believe everything you said. But
Remember when the Earth was flat, can't put a man on the moon, team going from last to first, horseless carriages, all these were impossible too. The pixels will shrink, we just might be around to see it. Lol

Couple of responses:

a) The fact that science once-thought the earth was flat, or that heavier-than-air-flight was impossible, does not .... ergo ... mean: "Anything is possible". No more so than saying it's impossible to fit the Empire State building into a plastic sandwich baggie. Someone could say "You can't say that's impossible because .... after all, they once thought the earth was flat". Does not logically follow.

b) As I said in my post: Even if/when pixel sizes shrink (even to 10x better, for example), you still do not get a magical X-ray television quality picture. You will just have a messy blotch of pixels. And that the moment you add the slightest tilt, you can kiss shape showing goodbye. You can't change the laws of physics. Heavier than air flight, for example, did not change the laws of physics.

c) Something entirely new and different would need to come along. Not just "faster and smaller" changes to existing knowledge/tech. There has reached a point of diminishing returns on the metal detection techniques we currently use (VLF, TR, PI, GPR, etc....). That's why you notice ground-breaking leaps and strides during the mid 1960s to the mid 1980s, when all of this was developed and invented. Right ? Back then if your detector was a mere 3 yrs. old, you had a dinosaur , haha. But now, we have machines 10 or 15 yrs. in production, that are every bit as good as current offerings. Because technology's "faster and smaller" has reached a point where the laws of physics are involved. If something altogether different, that doesn't rely on existing transmit/receive methods, then there might be something to talk about.

avatar
A small 'mag' for adding to detectors was made in Oz called the Ferrous Hound
Posted by: vlad
Date: September 01, 2017 01:26PM
It could be clipped onto the loop or shaft, & could be left turned on, or as needed. It would work on large iron but not very well on small,
Objects like a nail, washer or bottlecaps were difficult; orientation of the object, vertical vs horizontal made a difference. (vertical worked better)
Jimmy Sierra tried it with his units and said it just did not work.
Consider it a first step showing promise with a lot of development needed. (Mr.Bill has some knowledge of the ferr. hound)



Edited 1 time(s). Last edit at 09/01/2017 01:28PM by vlad.

Re: Got to be a reason. Fish finder vs metal detector
Posted by: Dancer
Date: September 01, 2017 03:33PM
Some of a lot of what I say is baseless or tongue in cheek. But there's new frontiers being made all over. Like cancer cures, time machines, the Military is tinkering with invisibility. Cloning ,time warps, we can't even guess what's coming next. Not long ago no one believed in life in outer space, global warming. Much of this hasn't been proven of course. But they just made driverless cars.
Does anyone really believe that metal detector science has hit the wall? I don't know how long it'll take, but when it happens it won't be by a quarter inch. Just saying.

avatar
Hit the wall.............
Posted by: vlad
Date: September 01, 2017 04:21PM
.....think its more a price barrier, and what the customers are willing to pay. However..........:look:
Barring a new incarnation of the PRG, it seems the P.I. will be the next big leap.
Look at their prices now, and they are relatively simple. Multiple functions breeds complexity which means higher prices--will the market support it?
(I'm told by George Payne some things have already been done in the commercial P.I. field, but they are very expensive--in relation to the current upper end hobby units.)

avatar
Vector scan? :lol:N/T
Posted by: vlad
Date: September 01, 2017 04:23PM

(This message does not contain any text.)


Re: Got to be a reason. Fish finder vs metal detector
Posted by: Tom_in_CA
Date: September 01, 2017 06:07PM
Quote
Dancer
.... Does anyone really believe that metal detector science has hit the wall?......

Yes. Current methods of metal detection, yes, maxed out. That's why you only see "whistles and bells" (re-packaged, snazzed up) stuff for the last 15 or 20 yrs. So to answer your question: Yes. Unless you meant something entirely different. But what we currently use to detect metal, will not be changed with "faster and smaller" electronics. Nor can you change the laws of physics.

You can not fit the empire state building into a plastic sandwich baggie , no matter how much cool science you apply.

Re: A small 'mag' for adding to detectors was made in Oz called the Ferrous Hound
Posted by: Tom_in_CA
Date: September 01, 2017 06:12PM
Quote
vlad
... Jimmy Sierra tried it with his units and said it just did not work....

I heard the same thing about Jimmy Sierra and this tech. And that you could point it at an enormous acres-large field, and it would tell you which portion of the field had iron (single nail?) in it. Ok, since when haven't any of us had trouble finding nails in fields ?

About the only thing this might be helpful for is if you could point the thing at multiple-square miles, to determine where concentrations of iron are. So that, for example, you can find cellar holes with no surface clues, etc.... But once you got there, you *still* pull out your standard metal detector.

This is the same logic as magnetometers for ship-wrecks: All it does is tell you concentrations of iron. Once you are there you still have to resort to standard detectors.

Re: Got to be a reason. Fish finder vs metal detector
Posted by: ROBOCOP
Date: September 02, 2017 05:39AM
Read about the Minelab GPZ 7000. On the Kellyco website you can review the operator's manual and see some specs. I found it interesting.

Re: Got to be a reason. Fish finder vs metal detector
Posted by: Dancer
Date: September 02, 2017 06:37AM
Quote
ROBOCOP
Read about the Minelab GPZ 7000. On the Kellyco website you can review the operator's manual and see some specs. I found it interesting.

Well for a hunter with experience and handy to sites bearing gold, this seems like something to look into. So 40% better than the Gpx 5000. Believable? You think there's been some type of break threw? Not for the great unwashed, but for a semi/Professional who got some good sites. Maybe. $8 grand , better have some proven sites in mind. Huh? Lots of home work to do on that.

for purposes of this thread ......
Posted by: Tom_in_CA
Date: September 02, 2017 07:14AM
Well, getting back to the initial question of the thread: "Depth". And the GPZ 7000 is a nugget machine. Hence, sure, awesome depth (1.5 ft. on a dime I bet !!). But the devil is in the details: Heaven-help the coin/relic guy who attempts to use such a machine for turf or ghost-town or cellar hole type hunting. The bells of notre dame will ring off every pinhead and staple. And he'll have no usable disc. beyond the first few inches, etc.....

Thus advancements in nugget machines is fine and dandy for nugget hunters. But isn't going to help coin/relic guys for all other hunting.

Sorry, only registered users may post in this forum.

Click here to login