Hey Old Bill, still a student of the new tech myself. But so far, SL mode brings on depth/read AND footprint from what I've sensed. I've been to some pretty trashy sites and some pretty clean ones.
Difference between these Fisher models and the old ones, the deepest targets may actually up-average in numeric readout. The exception seems to be the IH and the wheatie down to the envelope. Seems both age/depth affect how they read.
My F70 reads coins well to 8" then they disappear. In that window, the deeper AND older the coin, the lower the target ID. Newer coins at depth read consistent from surface to 8". I have proven this to my satisfaction at a recently opened park in town here where I've dug many clad quarters from surface to 8" and they all id'd nearly identical in the 82-84 range.
Same goes for clad dimes though they ranged slightly wider from high 60's to low 70's. Copper mems seem a dead giveaway at 70-72 although many clad dimes fall in there also. Zincolns are still in there, only the higher-range IH's read like zincolns on this unit.
Meanwhile the only 10" coin I got from there was from an old ballfield, a deep early teen wheatie that read like a high-dime to low-quarter range with an occaisonal bounce into the 90's. No iron numbers there either.
Both silver dimes and silver quarters read higher than their clad counterparts. Silver dimes I've dug come up 74-78 depth-dependent with one at 80, silver quarters from 84-88 again deeper or slanted or rings higher, on edge rings fairly standard values both clad and silver. That's once you've established pinpoint to the angle and direction of coin. Sweeping across an edged coin gives you the bouncy numbers, but along it's length in a slow, tight pattern you get the best read and can tell pretty much what it is.
But remember, you pretty much have to run the unit wide-open to get these results. I keep it a 0 disc, dE, 90 or better sense. I vary thresh as conditions allow from -1 up to 5, use 3h tones and I'll notch anywhere from 1-4 to quiet the iron down. Nice thing about using the notch is again the tendency of this machine to up-average coins instead of down-averaging them. Some of the odler machines you had to listen for the iron bounce to get the right read on a target, not this one in my experience.
Only use SL in quiet environements, it does up-average trash to good target status and again, increased footprint means reduced effectiveness of the primary component, the DD coil.
Okay, true story time: Earlier this spring I hunted with Treasurefiend and a few others. Trashy place, got nothing for myself there. Fiend asked me to check a target his SE was mixing up. Swung at it from a couple directions and found the right range on each side to tell him I was seeing a mem cent within an inch or so of a wheat cent. Two targets not one but too close to call from any other angle. He called me back over when he dug the mem cent, then found a wheatie an inch under it and slightly offset.
I think you'll like the nuances of the machine once you start discovering them.
