I would like to comment on this thread.
Recently I have been thinking of this....
Couple weeks ago I did a simple air test.
Oh boy another air test.
Auto+3 gave me a silver dime at 4.5 -5 inches
just changing to manual same silver dime 6-6.5 inches.
Running in Auto and missing deeper targets in my opinion is a fact.
So my thought is get the biggest ideal coil (15x18 SEF) comes to mind and still run in Auto+3 and by having the bigger coil will make up for any loss in depth.
I know you can run in manual higher sens, with the bigger coil, but wouldnt it be nice to run in auto+3 and still pick up a silver at 10" every now and then?
DD
One thing I really learned from swinging a V3i was that jacking up Sensitivity does not help depth much, greatly increases false signals, and kills ID.
Your post got me wondering and I made a Video. https://www.facebook.com/RieselPolice/videos/1812207052401485/ In short your findings are right on.
Here is a picture of a hole I dug today that had a Wheat at the bottom. This is a Mars Pinpointer so it is longer than a Carrot. I am pretty sure this was a full 8" with a Coiltek 10X5 coil. This place is running me nuts with Crushed Screw Caps.
See Edit below
Well I may have to edit that 8". I took the time and measured my Mars Pinpointer and it is actually 10" long.
If it's iron that's the problem,running in Ferrous sounds is the thing to do,with a wide open screen,no disc. Why? The audio is ALWAYS working,NO nulling. The background is a constant drumbeat of iron,and the non-Ferrous comes through brilliantly.
I've run ML's for years. I rarely if ever use AUTO sens because it absolutely kills my depth capability. I normally run 28 manual.