The detectors I use and have used over the years would detect deeper in all metal than in discrimination. There were others that had the all metal sensitivity reduced so it was the same as the discrimination but I think that gave way to better judgment of giving users greater depth in all metal.
My detectors appear to default to a low tone if a target is past the critical detection depth of discrimination. This makes sense to me or the user is going to dig a lot of very deep holes only to find junk if it defaulted to a high tone. What do we do about those targets that we can detect in all metal but not in discrimination? I noticed on the T-2 forum a heated debate about bottle caps that is not in my opinion a design problem but giving the user what they want issue. Unfortuantely killing bottle caps is going to mean less sensitivity to some desirable targets. We can kill bottle caps and screw caps with the Explore but with the understanding that a good target that his in that area is going to be rejected. It is the same with a pulltab and ring as we know.
Let me make a few suggestions with the idea of finding the deeper good targets. The selection of coils is very important. A coil has a physical and electrical footprint. The electromagnetic footprint is the target volume and includes all conductive materials. There is a major demand placed on the electronics to distinguish and present to the user in an effective manner the individual targets in a way that we can isolate to good ones. The more individual targets there are in the target volume the more difficult this is. If we use discrimination then an algorithm determines if an individual target in the target volume is presented as a good target.
I have extensively tested coils and targets at different angles to the coil and in different configurations and numbers. I have used free air and targets in the soil matrix. It is critical, in my opinion, that we understand depth of detection. An off hand example of what I am talking about is it is not how hard the ball is hit that makes it a homerun but that it is over the fence within the playing field. The coil can detect so many targets and or the settings can be so high that we get no depth on targets that are well within range of the detector. No matter how we sweep the coil and how long we have used a detector we get no depth on the target simply because the target will not be presented to the user as good. A stock coil is a general purpose coil and most are too large for trashy sites which are why most manufactures offer, as an accessory, a smaller coil. We may get mired down in the raw detection range of a smaller and larger coil but in trashy soil the smaller coil will greatly outperform the larger coil. I personally do not detect trashy soil with a stock coil but use the smaller ones. So, coil selection is very important in my opinion.
The second problem is discrimination in that we discriminate too much and there is a difference between detection depth in all metal and discrimination as I mentioned above. It is the difference in detection depth that can be effectively addressed as follows. An ultra deep low sounding target should always be investigated in my opinion. Coins are symmetrical while most trash is not. Symmetrical targets will most often give a sound that is the same if we sweep the coil from several directions. Trash targets will change sounds or breakup. This is what I use to determine if I am going to dig an ultra deep low sounding target. If the low tone indicates a symmetrical target then I dig it up. This actually is fairly easy to determine in that a nice consistent low tone when the direction of sweep is changed is what I am calling a symmetrical sound. I dig those targets.
There are other targets that have mixed sounds. What they are telling us is the target is co-located or is generating different time constants that are being reported to the user. As an example some targets are on the fringe of detection so are reported as a low sound and a high sound. The processor cannot seem to decide which way to report the target. Coins at angles will gives these sounds and often are being influenced by other targets within the target volume. I always isolate and dig these sounds.
What I don
My detectors appear to default to a low tone if a target is past the critical detection depth of discrimination. This makes sense to me or the user is going to dig a lot of very deep holes only to find junk if it defaulted to a high tone. What do we do about those targets that we can detect in all metal but not in discrimination? I noticed on the T-2 forum a heated debate about bottle caps that is not in my opinion a design problem but giving the user what they want issue. Unfortuantely killing bottle caps is going to mean less sensitivity to some desirable targets. We can kill bottle caps and screw caps with the Explore but with the understanding that a good target that his in that area is going to be rejected. It is the same with a pulltab and ring as we know.
Let me make a few suggestions with the idea of finding the deeper good targets. The selection of coils is very important. A coil has a physical and electrical footprint. The electromagnetic footprint is the target volume and includes all conductive materials. There is a major demand placed on the electronics to distinguish and present to the user in an effective manner the individual targets in a way that we can isolate to good ones. The more individual targets there are in the target volume the more difficult this is. If we use discrimination then an algorithm determines if an individual target in the target volume is presented as a good target.
I have extensively tested coils and targets at different angles to the coil and in different configurations and numbers. I have used free air and targets in the soil matrix. It is critical, in my opinion, that we understand depth of detection. An off hand example of what I am talking about is it is not how hard the ball is hit that makes it a homerun but that it is over the fence within the playing field. The coil can detect so many targets and or the settings can be so high that we get no depth on targets that are well within range of the detector. No matter how we sweep the coil and how long we have used a detector we get no depth on the target simply because the target will not be presented to the user as good. A stock coil is a general purpose coil and most are too large for trashy sites which are why most manufactures offer, as an accessory, a smaller coil. We may get mired down in the raw detection range of a smaller and larger coil but in trashy soil the smaller coil will greatly outperform the larger coil. I personally do not detect trashy soil with a stock coil but use the smaller ones. So, coil selection is very important in my opinion.
The second problem is discrimination in that we discriminate too much and there is a difference between detection depth in all metal and discrimination as I mentioned above. It is the difference in detection depth that can be effectively addressed as follows. An ultra deep low sounding target should always be investigated in my opinion. Coins are symmetrical while most trash is not. Symmetrical targets will most often give a sound that is the same if we sweep the coil from several directions. Trash targets will change sounds or breakup. This is what I use to determine if I am going to dig an ultra deep low sounding target. If the low tone indicates a symmetrical target then I dig it up. This actually is fairly easy to determine in that a nice consistent low tone when the direction of sweep is changed is what I am calling a symmetrical sound. I dig those targets.
There are other targets that have mixed sounds. What they are telling us is the target is co-located or is generating different time constants that are being reported to the user. As an example some targets are on the fringe of detection so are reported as a low sound and a high sound. The processor cannot seem to decide which way to report the target. Coins at angles will gives these sounds and often are being influenced by other targets within the target volume. I always isolate and dig these sounds.
What I don
Huh...I could of sworn thats what I said...The ferrous made me dig it but it was not very conductive (high)on smart screen...