New to the V3 a few questions....correlate

[earthmansurfer]

Funny coincidence Jack. I was searching through a European users posts here (bfodness) and came across this post of yours which re-affirmed a suspicion I have regarding recovery delay perhaps playing a big role with Correlate (bolded below) I hope you don't mind my repost. If anyone wants to see the context of the exchange here is the thread: http://www.findmall.com/read.php?66,1389943,1390443#msg-1390443

...A smoother start and end to the tone, Less beep like, more food for the ears and brain in the target tone.

Easier to hear a blend of two close targets too

Using Tone ID in combination with a slow Recovery Delay (90 to 110) you will get this effect. You must have each VDI assigned with it's own tone and incremented by one. The Default Coin or Coin and Jewelry is set this way. This is actually how I pick out good deep targets. Rusty nail tips which can present themselves as a good target at times will sound different. Typically the high tone will be cut off sharp on a nail tip. The tone will roll smoothly on a uniform target such as a coin or ring. the ramp up and decay of the tone can tell you a lot. This requires a steady and slow swing. The slow Recovery Delay will still work well in heavy iron using Correlate modes. The V3/V3i really shines in this situation, as it will prioritize it's response based on the dominance of the targets. This usually gives the coin the advantage without having to rely on separation of targets. It's why we find so many targets together in the same hole. I hunt old parks and this is very common. Most detectors will mask in this situation. On a side note I have found many more deep coin spills as well. Even multiple good targets can appear as trash, as it will confuse the filters of a lot of detectors.

Jack

I will have to test a slower recovery delay (which will rule out hammereds, but that's ok) next time I have a chance to test correlate. You guys playing with correlate and not getting results, I'm curious to see how upping the recovery delay changes things.

What is further interesting though is that I made a post regarding "flute like sounds" with the V3i and here you also talked about it (underlined). You really explained what took me a paragraph to explain quite well!

This machine is really really interesting for me...

EMS

 

[Schultzie]

Let me say this... I always read Jack's posts on correlate programming. He has been learning this for several years now and I followed him on other forums with the DFX also. I do not have the time to put into learning this (wish I did) and that is why I read everything he posts concerning it. Thanks Jack for sharing your learning curve with us! I understand the premise that a detector is only as good as the person swinging it.

 

[CyberSage]

Hello Schultzie!
Nice to hear from you friend. Hope all is well with you. You are too kind. One of the things I really enjoy about detecting is sharing discoveries and experiences with equipment and technique here on the forums. For me it is an unending learning experience. We all now that learning how a given detector is designed to work, and then familiarizing ourselves to the nuances of the machine itself, are different things altogether. As you have stated so wisely, there is only so much time in a day, so taking advantage of each others experience is a must.

Jack

 

[earthmansurfer]

Well, I got correlate to work better than best data and I'm pretty happy! I went out back and tested a 9" Nickel and a 4" hammered. We had some rain last night and before noon. My garden is FULL of iron and trash from WWII - it is bad, worst I have ever seen. A true testing area. Nickel in the ground less than a year, hammered around a month.

I was running a sensitivity of (Rx 10, AM 70, Disc 90), Filter 5 band and recovery delay 32. There is no place to GB in my yard but I still had the unit GB'd from the park and generally this area is at -91.At first it was the same thing, best data gave a better signal (on the nickel, didn't test the hammered yet.) Oh, I was using the 6X10 coil.

I then moved the filter to 7.5 - nothing, then 10 band, bamm, like magic I was now getting a signal, though not good. I played with best data and got a decent signal too. Correlate was better, but barely. I then moved the recovery delay to 80 and slowed my swing down. Later I did play with it at different settings between 32 and 80 and actually liked 80 on both coins (shocked me on the hammered). I didn't like the signal with the recovery delay at 32, regardless of best data or correlate. It was too sharp and cutting out but I come from the T2 and Omega so am a bit used to that. There is iron all around the coins, the 5 tone doesn't let up. The Nickels VDI is very very high, ranged from 55 to 93. I imagine the yard is full of iron flakes to do that. My Omega won't even chirp on these coins. My spectragraph was very very clean though as I run it in consistency. There was some red on right edge of the green. In the field it could mean iron but the signal was too good. It looked like Southwinds screen. I'm not rejecting anything btw.

I was able to get a pretty good repeatable signal with 10 band and recovery delay of 80 in Correlate and best data. I'd say Correlate improved the signal by 20-30%, sometime more, sometimes less. I tried this out on the hammered coin (small thin, dime sized, VDI 15.) and got a signal too! I'm really shocked at this point and wondering how much the rain changed things as well as the settings. The VDI of the hammered was in the range of 13-17. Both signals would be dig me's but to be honest you'd have to be overlapping your swings 50% to hit either as the iron is just too much, plus non ferrous trash. The filter was more important than recovery delay overall.

With my 5" Excelerator coil I can get the hammered too, but the 22Hz freq is best. Worth noting that correlate worked slightly better than best data with the 5" coil. I could on and off hit the nickel with it and was actually able to local an 8" buried dime that I couldn't hit at all with the 6X10, I'm sure thanks to the rain. Very doubtful that I'd hit it in the field as I had to be really on it. But it was mostly repeatable and gave a depth of 6" with a coil size of 4X6 selected.

I have some testing to do in the field now, with the filters first. I will stick with a recovery delay of 80 as bfodness said he uses that in Norway for deep silver with the 6X10 and correlate I believe. At least I have come over to the correlate side where as my last testing made me not even attempt it any more. Thanks for the inspiration Jack. Many thanks and I'm really curious to see if others can get correlate working by playing more with the filters and secondarily recovery delay.

 

[earthmansurfer]

I played in the garden more today and now I was able to pick up the deep Nickel with the 5, 7.5 and 10 band filters (The high filters didn't seem to work well at all). I guess the rain affected the ground a lot.

Also, on the Nickel running correlate today the signal was around the same as best data, where as yesterday correlate was better. But on the 4" deep hammered correlate was still clearly better! I will just have to find a deep target in the field to really get a better idea on correlate but again, now it is picking up the coins AT LEAST as good as best data and that is great news.

 

[CyberSage]

Great Field notes EMS. Thanks for making the effort to share with us. Good study you have going. Keep us up to date.

Jack

 

[earthmansurfer]

Thanks Jack. I'm a newbie but putting in the time to learn.

Here is a short video I made (my second) comparing the signal on a 9" buried Nickel with Correlate and Best Data. I'd say Correlate wins this time.
Rx@10, disc@90, Filters varied, Recovery Delay 80, Ground is probably non mineralized but with medium to high iron mineralization content. (last time I was able to check it). It might be higher as the 10 filter worked best and in my other sites it doesn't work. Not sure what it could be exactly. I didn't ground balance in the video as there is no place to ground balance in my yard.

[video]http://www.youtube.com/watch?v=hklwtYZMlro[/video]

 

[Low-Boy/LCPM]

The VDI I hear as a low grunt iron maybe a tone of 5 on your machine I wonder if it would be better to give it a 0 tone like I do..It seems you can hear more that way. My runs cleaner less noise and works better for me.

 

[earthmansurfer]

Hey LowBoy, I have to play with tone 0 on iron. I started with just a low tone but that was too much audio fatigue.
The problem with running 0 is I have to be looking at the meter to see when I hit iron. I don't mind the low iron tones as it helps me to focus more in that iron. But then again, if I'm in an area with non stop iron, I might as well try it! Thanks for the suggestion.

 

[Low-Boy/LCPM]

My threshould goes quite when I am near iron so but I hear the tone of the VDI I except

 

[earthmansurfer]

Thanks again Lowboy. I run with a soft threshold and noticed the fade out over iron. Again you are right! I have to try running tone 0 with threshold. Learning learning learning.

An update - Regarding the High VDI of the Nickel. I wanted to see if I could lower it as a user pm'd me and said to run in autotrack (Fox). So, after that last video I started playing with using autotrack in my yard over the target. I didn't want to use it because the yard is non stop chatter. But I tried it and not only did things clean up a little but the VDI's came down as well. My GB wasn't too off judging by the rare arrows but it was off a little. The VDI's now hovered between 19 and 60 or 70, with the average being somewhere in the 50's. A big improvement. Again, I need to optimize the GB as the V3i is just too sensitive (thankfully so - it gives us the depth it seems).

On a correlate related note, I played with lowering the span from 45 to 30 to see if that would help lower the VDI per another suggestion. It seemed to lower it some as well. I also noticed that I was getting less or rather no red (to the right of the highest VDI) most of the time in the test - I think from the better GB?. I played with a lot of settings, recovery at 80 and then 50, all the filters between 5 and 10 (5 band and 10 band were best - rarely does 7.7 work at all. It's almost like it doesn't fit in there. I mean how could 5 and 10 work great but 7.5 gets hardly a signal???) Lowering Rx from 10 to 6 might have been the best improvement.

Heck, I might as well upload the video as it speaks louder than words. Not much of a video but still interesting to watch as you can see the effect the adjustments have if any. The machine was in locktrack as I forgot to put it in autotrack, which I should have considering I changed Rx, etc.

Thanks and I hope this was of some help,
EMS

I recommend you watch it in 720 full screen (at youtube) so you can see the settings.
[video]http://www.youtube.com/watch?v=m8V5tDt9A5w[/video]

 

[Rob (IL)]

You need to lower your gains until you just can get the target signal. Then you will see which filter is the best. If the signal is too good even the filter that is not the best will work. The same for any setting you need to optimize. ROB

I accept all VDI and set the VDI I don't want to zero. In your case try rejecting the iron VDI range as well as setting them to zero and use visual reject. Then set your base threshold to 90. See what your spectragraph looks like. you might also set the resolution to 7. This will give you fewer fatter bars. It should be cleaner.

 

[earthmansurfer]

Thanks again for the comments Rob. Yes, I'm aware of what you said regarding the filters. I sort of did that spontaneously while filming. BUT I'll make sure not to make that mistake in the field! And for sure I will GB when changing those settings (though today I ran autotrack and it worked very very well in the iron.)

I took Lowboys advice today and had the iron tone at 0 and I also discrim'd out -95 to -71 & 95. It was so nice and quite on my hunt today. I started finding coins immediately after making the switch. The threshold told me where the iron was. I'm embarrassed to say this was a new way for me to hunt, but I'm still getting used to the V3i. My SAT was at 20 but with the iron being more on the heavy side I think I should lower it so I get a better idea on the iron. Any suggestions for a SAT setting? Visual reject was on and resolution is set to 7, just checked. My base threshold was at 80 for my hunt today. I think you mean when I'm in heavy iron and trash to not have the base threshold as "open" and run it at 90?

Thanks again, I'm learning so much,
EMS

 

[Rob (IL)]

SAT has no affect unless you are hunting in all metal, mixed mode, or stereo mixed mode. It only affects the all metal channel only. Leave it at 20.

In trash, a lower number on the BT will give you a more noisy spectragraph. You will see more of the weak signals from the tiny bits. The lower number (65) gives more info but is more busy. Except for the hot programs like Hi Pro all the others run the BT at 90. This will clean up the screen.

You now have the ground VDI rejected and the iron VDI set to zero.

ROB

[size=large]This post is really long and hard to follow. Lets start a new one.[/size]