Recovery Speed In Relation To Ground Mineralization

[midalake]

Today, I tried to lower the recovery from 6 to 5 on my beach. I was unable to hunt at 22 sensitivity anymore and would have to lower to at least 21 with black sand interference still audible. After 20' I returned to 6 recovery. 

[Digalicious]

Thank you for the additional replies.

Yes, the higher recovery speed tightens up the signals, but I just don't get the part of, "Recovery speed 10 is way way way deeper in my mineralized soil than 5".

Perhaps the slow recovery allows much more of the mineralization to come through, which could mask the deeper weak targets, but "way deeper" ??? Especially considering that there is an "in air" depth loss of about 4" when going from 5 to 10 on the recovery speed.

 

 

[Digalicious]

Hmmm.

Now I'm wondering if he is actually able to significantly increase the sensitivity along with increasing the recovery speed. That could account for the depth increase. I'll have to ask about that, but he's tough to get a hold of with all the comments that are posted in his videos.

[midalake]

34 minutes ago, Digalicious said:

Now I'm wondering if he is actually able to significantly increase the sensitivity along with increasing the recovery speed.

I bet he is able to increase sensitivity. As compared to lower recovery speeds.  

[EL NINO77]

3 hours ago, Digalicious said:

Thank you for the additional replies.

Yes, the higher recovery speed tightens up the signals, but I just don't get the part of, "Recovery speed 10 is way way way deeper in my mineralized soil than 5".

Perhaps the slow recovery allows much more of the mineralization to come through, which could mask the deeper weak targets, but "way deeper" ??? Especially considering that there is an "in air" depth loss of about 4" when going from 5 to 10 on the recovery speed.

 

 

First, let's ask ourselves a question... what is hidden under the name recovery sped?
   The degree of certainty of recovery sped is actually the setting of two parameters: the certainty of the type of ground filter and the time of operation/recovery/ of this ground filter.
   These two parameters are optimized for each level of recovery sped... and in general, it is the case that the higher the group filter is set, the faster the recovery work of this filter is.

   In general, it is true that a certain value of recovery speed will be the most optimal for the day type of mineralization of the terrain.. because too low a recovery will not filter the signal of the terrain well and may also be unstable ..-and therefore you will not find deeper targets...
and..on the other hand, if the recovery speed is too high, the detector will become very stable, but in such a terrain.. it is shallow ... and therefore you will not find the deepest signals either...

But if you set the optimal recovery speed ... for this terrain ... then the detector will be sufficiently stable and will also have an optimal depth in such terrain...

[Guest]

6 hours ago, EL NINO77 said:

First, let's ask ourselves a question... what is hidden under the name recovery sped?
   The degree of certainty of recovery sped is actually the setting of two parameters: the certainty of the type of ground filter and the time of operation/recovery/ of this ground filter.

Indeed. It can also be looked at in terms of what it does in the context of the whole machine. This is how I do it because I lack technical understanding of the engineering of these machines.

I think of recovery speed as how long I am giving the detector to look at something before it looks at something else. Mineralized soil has a lot going on in it, so if you do not shorten up the time to look, too much winds up in the picture and it is a jumble that gets noisy and difficult to sort out. If the time to look is too short, it clips off part of what should be in the picture, and you have poor signals because you don’t look long enough.

Thinking in such terms it can be seen how recovery is dependent not just on mineralization, junk etc, but in fact on how fast you sweep the coil and what the other settings are doing as well. It is always a compromise in all but the mildest of soils because of what the detector has to do to keep up and what you are telling it to do with all the other settings.

Detectors do so much these days it is hard for me to keep up with it, so I look for a way to visualize how the settings are balancing what the detector does and this is how I think of it when I am using the marvelous control we get these days. Balance is entirely dependent on conditions, so we are always making the best of what we have. The fella is squinting his detector into the harsh sun of the mineralized ground, and a little sun glass action lets him open the eyes a little more and see a little further.

Old man rantings, your mileage may vary.

[Digalicious]

Thank you again for the additional replies.

I now understand how in highly mineralized ground, a higher recovery speed will go deeper due to the detector not "seeing" as much of the mineralization. I can see how that would allow the targets that are close to the same signal level of the mineralization ground, to be detected better. But, "way, way, deeper" as he said? Well, I think that might be a little bit of an exaggeration, or we have a different idea of what "way deeper" means 🙂

Then again, the swing speed is related to the recovery speed. He has an extremely fast swing speed. That fast swing speed combined with the high recovery speed would also be a factor in getting more depth in his highly mineralized ground.


 

 

[EL NINO77]

2 hours ago, Geezer said:

Indeed. It can also be looked at in terms of what it does in the context of the whole machine. This is how I do it because I lack technical understanding of the engineering of these machines.

I think of recovery speed as how long I am giving the detector to look at something before it looks at something else. Mineralized soil has a lot going on in it, so if you do not shorten up the time to look, too much winds up in the picture and it is a jumble that gets noisy and difficult to sort out. If the time to look is too short, it clips off part of what should be in the picture, and you have poor signals because you don’t enough.

Thinking in such terms it can be seen how recovery is dependent not just on mineralization, junk etc, but in fact on how fast you sweep the coil and what the other settings are doing as well. It is always a compromise in all but the mildest of soils because of what the detector has to do to keep up and what you are telling it to do with all the other settings.

Detectors do so much these days it is hard for me to keep up with it, so I look for a way to visualize how the settings are balancing what the detector does and this is how I think of it when I am using the marvelous control we get these days. Balance is entirely dependent on conditions, so we are always making the best of what we have. The fella is squinting his detector into the harsh sun of the mineralized ground, and a little sun glass action lets him open the eyes a little more and see a little further.

Old man rantings, your mileage may vary.

How fast you sweep with the coil at a certain recovery speed will strongly depend on the mineralization of the terrain ... because in lightly mineralized terrain you can also sweep at a fairly low recovery speed ... relatively fast .. and you will still receive a signal from the target from both sides of the coil sweep every time ...even on deep targets..
 
The problem starts if you go to detect at a similarly low recovery speed in more mineralized terrain... and with a quick sweep with the coil you start to pass deeper targets....
..That doesn't mean that you won't find shallower targets... Yes.. but you won't be able to reliably detect deeper and deeper targets...or not at all..
   ..
A good advice is if you have a detector that has a fixed lower ground filter/recovery sped/ it is to slow down the coil sweep speed in such terrain... and thus enable the detector to optimally detect targets in such terrain...

If you have a detector that has an adjustable recovery speed, then in such a terrain, increase the recovery speed to a higher value/ the best optimal for this terrain... and then you can sweep the coil again at normal speed... and you will be able to reliably detect even deeper goals...

what is the optimal recovery speed for the given terrain? That - will depend on the strength of mineralization of the terrain...

Furthermore, it will also depend on the degree of contamination of the field with iron, because the higher recovery speed does not see the iron from the side of the coil as far as it is with the low recovery speed, and therefore the higher recovery speed better unmasks good signals in the field... which is covered with iron waste..

  if you are starting detection in some terrain... normally I recommend using medium high recovery speed...

[Guest]

21 minutes ago, EL NINO77 said:

what is the optimal recovery speed for the given terrain? That - will depend on the strength of mineralization of the terrain...

Furthermore, it will also depend on the degree of contamination of the field with iron, because the higher recovery speed does not see the iron from the side of the coil as far as it is with the low recovery speed, and therefore the higher recovery speed better unmasks good signals in the field... which is covered with iron waste..

Quite so. The trade off for faster recovery is depth, and the more mineralized it is the harder it is to balance. The balance we have to strike is always dependent on conditions.

The first thing lost is as you say, deeper targets. Also smaller ones. And deciding which way to balance is also dependent on what we are after. The reason sensitivity falls in here is because you can use a little more of one if you use a little less of the other, and which way you balance is a function of what you are doing and where.  Hunting silver coins in iron is much different than hunting gold jewelry in junk aluminum.

Excellent discussion El Nino77. I really appreciate your technical knowledge of the subject, especially where it concerns unmasking. I consider that the key outcome for all this. We want good targets to separate out from the ground without falsing and be distinct from the junk. Easier said than done some days.

[Digalicious]

Despite not having to contend with highly mineralized ground, many of my hunting grounds are old residential buildings that have been torn down. These sites typically contain very little nonferrous trash, but they are the proverbial "bed of nails". Due to that bed of nails, then in a sense, it's "kind of" like having highly mineralized ground. 

I find that my default mid recovery speed is very fast, but in those iron infested sites I usually set my recovery speed to medium high, but never max it out. Additionally in these sites, I'll use a small to mid sized coil, a low iron bias, higher frequencies, and a slower sweep speed.