Rick, discrimination is merely a tool that helps us get the most goodies for the least amount of work. I am reminded of an article I read a few years back about a British journalist who spent 7 days detecting a old field. Hunting in the "all metal" mode, he dug ALL targets, and dug something like 1,077 targets in that time. Of these, something like 1,010 were iron, the rest were non-ferrous. Yeah, much of that was junk. But 32 of those were Roman metal items, mostly coins. I would guess that, using iron-level reject, the journalist could have covered that field in a day, and might have gotten (perhaps) half of the non-ferrous items. See the difference? If we "dig every signal" we will miss very little, but the ratio of good finds per hour will drop significantly. Thus, the use of discrimination helps us to improve the odds of finding good stuff. On your MXT, the first arrowhead on the dual control misses most iron targets, as well as most pieces of foil. As for myself, I use a tiny bit higher setting, about a 1/16 of an inch clockwise from that little arrow. This insures a bit better iron reject, and a lot better foil rejection. Of course, this may be due to the characteristics of my own machine, or my soil conditions, so you should give it a try under your conditions. Using a discrimination setting of 1 will accept almost all targets, putting you back into the "all metal" operation. Remember, use as much (or as little) discrimination, as needed, to accomplish your goals. Hope this helps; HH Jim