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#26
03-23-2007, 06:06 PM
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- Carl 
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#27
03-23-2007, 07:58 PM
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Too many.
Thermal emissions, radioactive emissions, etc. Most of those are undersestimated as is the radioactive power released. Earth’s bulk iron core has a high oxygen isotopic ratio. Add to that, recent studied rare emissions in the thioindates.
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#28
03-23-2007, 09:23 PM
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#29
03-23-2007, 10:24 PM
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#31
03-24-2007, 01:40 AM
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- Carl
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#34
03-27-2007, 06:25 AM
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Preliminary study with IR thermometer treasure hunting (Long Post Alert)
Yesterday I made a preliminary study to learn something about using an IR thermometer for treasure hunting. I took an infrared thermometer with similar specifications to the Mastech MS6530 to the beach to see if there was any promising indications that it can be used for dry sand hunting. The thermometer was an inexpensive Alltrade model #480742, with a 0.1 degree resolution, single laser pointer, and D:S ratio of 10:1. The D:S ratio of 10:1 is fairly close to the 12:1 ratio of the Mastech MS6530, but the slight difference is not important in the close range study I conducted.
The purpose of the study was to see if this thermometer would pick up any usable readings from coin-sized objects buried in the local beach sand. If I could find some consistent readings over coins and other buried objects, then It would warrant further testing to determine how to detect these objects in the sand. I brought along a collection of small objects to bury that included the following: New US dollar coin, silver quarter, clad quarter, sterling salt shaker 1.5" tall, sterling silver ingot 1"x2"x1/2" thick, 0.8 gram sterling silver ring, 7 gram 14K men's ring, 3.5 gram 14K womans ring, new US nickel, gold plated men's watch without band, clad dime, clad penny, aluminum dog tag 1.25 inch dia on a steel ring, aliminum clip 1/2"x1.5"x1/16" thick, nugget of melted aluminum 1"x1/2", 2 brass keys on a steel key ring, toy cast zinc car 3" long, 16-penny steel nail, 2 stainless steel buttons, 1-tablespoon stainless steel measuring spoon, bent copper strap 3"x1/2"x1/32" thick, 3-oz flat lead fishing weight, 1-oz oval lead fishing weight, lead sheet 1.5"x3/4"x0.10" These items were chosen because they have different heat transfer properties, and are items that could be expected to be found on a beach. (in fact, all of them were found on the beach except the silver ingot and the nail). I also added a steel pliers/knife tool to see if a larger object would make any difference. The study was performed in hazy sunshine with a cool 60F degree breeze coming from the ocean. Before conducting the study, I marked a 3-foot by 6 foot area of the sand to bury these objects. This area was located about 2 feet vertically above the high tide line in dry sand. I scanned the area with a VLF metal detector and removed all the metal targets I could find within 2 feet of the test area. Then I raked through the sand to remove any pebbles over 1/2 inch size. I took preliminary readings I took temperature readings from 6 inches above the surface. I found the sand temperature varied between 78F degrees and 110 degrees depending on where the shadows were. In order to eliminate any cool readings from shadows, I dragged a board over the sand to smooth it so there were no shadows, and waited a half hour for the temperature to stabilize. at the end of this time, a survey showed that the temperature varied between 94 and 106 with as much as a 5-degree gradient over a 1-foot area of smooth flat sand. I waited another half hour and found no change in the temperatures. Further investigation showed that the sand was damp below the dry sand at depths that varied from 4 inches to 7 inches in the test area. It seemed likely that the non-uniform damp sand beneath could be influencing the surface temperature. After checking other areas of the dry sand, I discovered this entire beach has the same uneven damp sand layer beneath the dry sand. So I used the test area and buried the objects with their top surface 1 inch deep to see if there were any noticeable changes in the areas where they were buried. After an hour had elapsed I could find no changes. I figured that maybe these objects need to be closer to the surface to be detected with an Infrared thermometer. So I dug them up an buried them at the surface, and I covered them with 1/8 inch sand over the top. 1/2 hour later I took readings, and found that there were minor variations in temperature where a few of the objects were buried that registered up to 1F degree. The problem was that some of these readings were higher at the buried object, others were lower, as in the case of several silver objects. But most of the buried objects showed no change in temperature where they were buried. For example, none of the gold or aluminum showed any change. The Silver ingot was 1F degree cooler, the silver salt shaker was about 1/2 degree warmer, the silver quarter showed no change. The steel pliers area was about 3/4 degree cooler. Sand is used as a thermal insulator in some heat-treating methods, as it helps buried metals to maintain their temperature. If I had to guess, I would think that the bulkier objects in this test retain their heat longer than the lightweight objects. I moved these objects from 1 inch depth of cooler sand to 1/8 inch depth, so I would expect the lighter objects to heat up more rapidly from conduction of the sand surface layer. But none of these temperature variations at the buried objects seems very significant when considering the temperature gradients of the sand area before burying these objects. If I also consider the high temperature variations caused by shadows from the footprints in the sand, I can't imagine finding any buried objects anywhere on the beach this day using an infrared thermometer. After running this preliminary study, I was left with a feeling that Infrared may not be a very good tool to detect small objects buried in the local beach sand. The biggest problem is the sand temperature varies with the shadows from footmarks in sand to enough to obscure the targets during the daylight. Second, it appears small targets need to be close to the surface in order to detect the small temperature variation at all in the daylight, and so far, I got no consistent readings on the buried objects. The cheapest metal detector can locate buried objects better than the infrared thermometer did in this study. Keep in mind this is only a simple study, not a definitive test. And my feelings are only applicable to what I experienced at this particular beach. I think that there still may be some use for infrared possibly for larger objects closer to the surface. If an object is buried in soil that allows bulky objects to heat up during the day, then these objects may retain their heat into the twilight and dark times. This may work better in regular soil than in beach sand. If such a condition of lingering warm spots on the surface exists, then I think a thermal imaging camera is a much better tool to find the warm and cold spots rather than an infrared thermometer. (Unrelated note: While I was waiting for the test area sand temperature to stabilize, I hunted the beach with my VLF metal detector and found a handful of coins and a 14K gold ring that I dug from 7 inch depth).
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#36
03-28-2007, 11:33 AM
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Although a good start, your test is incomplete and may not garantee precise conclusions.
1 - If infrared can indeed be used for treasure hunting, then the most propicious time of day to perform the tests would be at night. When the surrounding environment (soil) is less warm and the metal object which might absorb heat and release it in longer periods than that of the soil. You did the opposite. In an already hot soil, you placed the objects and waited for them gain heat. 2 - The manual of the DIS300 which I had acess says two importoant things. First that noble metals behave differently than common metals regarding heat absorption and release. Second, it also leads to believe the device was somewhat modified for treasure huntiing , hence two different settings on it. Wheter this is true or not I or somebody will have to perform a test (according to the procedures the manual covers) in order to know if this is true or not. 3 - Beaches may not be good soil environments for those kind of tests. Sand temperature varies dramatically depending on what section of the beach you measure, besides the fact that it's highly rich in Cl and Na. A test in other soil shall be necessary. Add to this the fact that all your tests were made in disturbed soil, when there's a chance of air present. A natural buried target will have the soil undistrubed and compact. Don't know if this might prove relevant in the end or not. But it's just a thought. Anyway as soon as I have time I will try to test a regular Mastech 6530 which I found in a store in Brazil, (although out of state) and the DIS300 to see if there's a noticeble difference or not.
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#37
03-28-2007, 04:03 PM
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My test was not intended to be complete. It was only a preliminary study:
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By smoothing out the test area, I actually created a pseudo-laboratory condition that does not exist in our local beaches. I expect this smooth area should give much better readings than the beach sand in the state as I found it. Yet the results I saw were still useless for me to use at this beach in the daylight, even if the entire beach were to be smoothed like the test area. In actual daytime beach conditions, there is no way this thermometer could find treasure except by accident. I did take some readings on undisturbed soil also. What I found is the soil was not as hot as the beach sand in general. Also that the shadows in the undisturbed soil were cooler than the sunlit areas. But the coolest temperatures I read in the soil were places where the soil was damp or wet. I noticed there was no temperature difference in the locations where my metal detector told me there was an aluminum can buried, and other metal trash. I did not bother to dig any targets in the regular soil areas, because the only targets I found were shadows and wet areas. As far as conducting night tests, I would not consider doing this with an infrared thermometer. In order for any instrument to be useful for finding treasure, it must be able to indicate the location of the treasure in a reasonably short period of time. It takes about a second for the temperature reading to stabilize, and you need to take hundreds of readings to scan a small area. If I wanted to test for warm/cold spots in the dark, I would use a thermal imaging camera that makes an infrared picture of the entire field of view showing very slight temperature variation. For finding small coin-sized targets, an infrared thermometer must be used at fairly close range because of the angle of its sensing beam. The Mastech 6530 views a 4 inch circle if held 4 feet away from the ground. This may be acceptable for reading a coin sized area on the ground within 6 foot radius of where you are standing. But to survey an area 60 feet away, you are sensing a 6 foot diameter circle of land. I seriously doubt you would detect a coin-sized area that had 1 degree variation inside the 6 foot circle that represents the single pixel of the infrared thermometer. But only testing will verify this. An interesting experiment would be to have someone place a gold ring that was heated to boiling temperature on the surface of the ground at 60 feet distance during the night, and see if the thermometer is useful for locating the ring. See if the person holding the thermometer can recover the ring from 60 feet. If not, try 50 feet. then closer and closer until it can be recovered. This will tell the limits of the range for this thermometer sensing a 100C temperature gold ring at night. I suspect that if there is any truth to the concept that buried gold makes measurable surface temperature changes, then you could repeat the same experiment by burying an unheated ring in the undisturbed soil. This will tell you if your thermometer can find gold at night. Your best test to see if the DIS300 has extra gold and cave sensors added is to take one apart and see for yourself. I am sure Carl will be happy to post photos of the insides of his Mastech 6530 so you can see if there is any difference. I would be surprised if you can find any extra sensors such as a tiny chamber with gold in it, or a tiny chamber with a miniature cave in it.
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#38
03-28-2007, 05:07 PM
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There are 2 modes. First you set in range, sensing the soil in 4 directions (N-S-W-E) to give a chance for the device collect temp data uniformily. Then you change to 'gold' and begin your search. Whenever there's a 10 degree variation, chances are you found something. Then aproach the spot and and locate the exact point of higher temp. Then move device sideways so you see how it will decrement. If it's a smooth change, you found somehting. If there's a violent variation then either it's a rock or unkown concentration. For a cave, the opposite in temp variation will happen. Besides your suggestion, I would like to hear other test suggestions from posters to be done when my friend gets the chance to try the device.
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#39
03-28-2007, 05:40 PM
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Another test has already been suggested in my previous post
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#40
03-28-2007, 07:47 PM
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Hi J_Player,
Could you please make another small test with your IR thermometer? Really simple --> Put on table (indoor) few paper sheets of different colour (black, white, red, etc..) and record Temp. readings for each colour (from same distance). I had IR thermometer while ago ... It was very unstable I belive this issue has not changed in few years..or what? Also all please remember what Geo posted on 08-31-2006 Quote:
My only thought on this: With IR-thermometers/cameras you can measure temp. of only TOP surface of ground which is in constant interaction with air.... Add to this vegetation, relief, wind. Hey what are you actually measuring??  If someone would like to achieve any real detecting this way: *Resolution 0.1 degree is not quite enough.. you can buy good 0.01 degree digital thermometer with RS232 interface for about 300eur. *Timing is quite critical... *Use a needle-type sensor to measure temp. directly under topsoil and vegetation (15cm). *Work in predetermined (marked) grid and record readings. *Plot the readings. You can not find coins, etc. But you can discover whole buried city  .I mean buried walls, ditches, wells, roads, BIG bronze statues  ...
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#41
03-28-2007, 09:37 PM
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Paper test
Hi Leto. Thanks for the info from geo. I just performed your test:
I put the sample papers on a carpet which is on top of my concrete garage floor. The carpet is high quality Dupont Tactess carpet for indoor use with no carpet pad under it. There is a fluorescent light fixture located 7 feet above these papers with two 40 watt fluorescent tubes in it. I placed a notebook with 32 yellow pages on the carpet and yellow notebook paper on the carpet and a white paper the same size on the carpet below the light. These papers were placed side by side with 1 cm spacing between them. I waited 15 minutes, then I measured the temperature of the papers by scanning all over the page with my Alltrade #480742 infrared thermometer held 6 inches above the pages. Here are the results I measured: Carpet temperature measured 5 cm away from all the edges of the papers: 17.5C to 18.4C Yellow notebook with 32 pages - temperature of top page: 17.8C to 18.4C Black paper strip at the top of the tablet (2cm x 21.5 cm): 17.6C to 18.5C Single yellow page on the carpet: 18.1C to 18.8C Single white page on the carpet: 18.0C to 18.5C These temperatures that I measured are not stable. They change every time you measure. I believe the temperatures measured depend on the air temperature and air currents in the vicinity of the paper surface. The temperature of colored objects in the sunlight is largely influenced by the radiant heat of the sun. The darker objects usually absorb more of the sun's heat than light colored objects. You can feel this by placing your hand on a dark surface, and then on a light colored surface in the sunlight. Indoor fluorescent lights at 7 feet distance do not supply nearly as much radiant heat for these objects to collect. My conception of treasure hunting with thermal cameras is similar to yours: it would be best suited to finding much larger objects that would retain large amounts of heat. And My conception is the reliability in locating these objects would be marginal to good, depending on the depth, the composition of the object, and the composition of the surrounding matrix. I doubt infrared sensing a buried object has anything to do with the electron structure change as Hung suggests, but is more related to specific heat and heat transfer properties, primarily conduction. My infrared thermometer is not unstable. It measures the temperature accurately and it will repeat it's results accurately. The temperature of the items I measure are often unstable. Do not expect good repeatability on objects like paper or other lightweight objects exposed to air currents. Otherwise you will be measuring the temperature of the air that recently contacted the object. J_Player
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#42
04-02-2007, 08:18 AM
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Observations with an infrared camera
Here is a page that shows a study of locating land mines with an infrared camera: http://www.ees.nmt.edu/Hydro/landmin...02_thermal.pdf
This study shows that it is difficult to find land mines with certainty using an infrared camera, and the success depends on the variation of temperature during the day as well as the kind of soil and the moisture content of the soil. They found that the best times to look for the buried mines was in a time range centered around 12 am and 12 pm. From what I read in this study, the success in locating buried mines can range from poor to impossible, meaning that you can find them sometimes. Note that these mines are massive objects compared to the coins and rings I was surveying with my thermometer, and the camera they used was more sensitive than my thermometer.
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#43
04-02-2007, 01:21 PM
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- Carl
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#45
10-09-2010, 10:14 PM
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Harbor Freight has them
I bought a Harbor Freight laser thermometer a few years back - works fine for me. Seems like I paid about $30 for it. I use it in the lab when doing experiments that involve heat to tell me if something is cooled enough for me to touch it or if the chemical reaction is finished or whatever.
I worked on various types of IR systems for the military when I was a consultant doing all things wild and esoteric like image signal processing and I can verify with Carl - IR is a waste of time as a treasure hunting tool.  Save your money and buy a good metal detector  or if you can dowse get a couple of coat hangers. Goldfinder
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#46
10-10-2010, 12:02 AM
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.... And you don't have the bad feeling you wasted $600 or $3500! Best wishes, J_P
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#47
10-10-2010, 06:42 AM
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Last days a person called me, he want my thermocamera. He want to make some experiments and after it to go for treasure hunting.
As he said me one of the team has a device who bombard the ground (i don't know with what rays) so after it the thermocamera has the ability to "see" the objects inside the soil. I did not meet him still. If i will go for the experiment, i will inform the forum Regards
__________________
Geo
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#49
12-05-2010, 03:09 PM
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It is also expected a thermal imaging camera will find large objects close to the surface more easily than smaller objects, and objects that are buried deep. I would expect you can find buried objects more easily when there has not been rain for at least a few days. My opinion is dry soil works better, but I don't know from actually finding treasure. I do know that variations in damp ground cause very large temperature changes which could mask the location of a large buried non-soil object. Best wishes, J_P
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#50
12-05-2010, 04:37 PM
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Thank you very much for your reply.
My theory: find out where the thermal imager was disturbed land. Excavated pit and buried. Buried pit is wetter, cooler .(??)In the disturbed soil may be buried metal.With a camera but not search metal land disturbance. A detector check.
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Linear Mode
