Target identifaction can vary depending on the mode you are using (Low Trash, High Trash, Ferrous-Coin, Ground-Coin). When you go into Pinpoint mode your detector becomes a non-motion detector. Not sure, but it might also bypass any of the modes you are using (It would be great if we could get a confirmation on this). Rusty nails have always been a problem....sometimes they give a good reading and just maybe, when you pinpoint it on the CTX it could show up as iron which, if true, can be really helpful in making the decision to dig or not to dig in the future.
I am switching over from the Explorer SE and whenever Im in doubt, the best thing to do is dig it and make a note of what your detector is saying. If you find the same thing happening again then dig it again to see if you were right in identifying whats in the ground. It can be fun playing the guessing game!!!
This is just my opinion on what could be happening...the best thing you can do is learn what your detector is saying by digging, digging, digging and digging some more.
Hope this helps
Ron L
These are just some of my finds that motivate me to keep digging "iffy signals"!!!!!
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