With a beep and dig, you only have the audio with which to make your decision. Tesoro machines have good audio but even so, you dig a lot of signals that turn out to be junk. With a visual ID system you have a lot more information with which to make your decision to dig. Weak, questionable signals are some times passed by, but if you had a meter telling you its a 9" deep target, and its registering "coin", you would certainly investigate. Meters are not perfect and are not 100% accurate, but they do give you more information. Junk targets on the Cortes, typically have erratic ID data: ID numbers jump around, bar graph indicator also is erratic. When I first got my Cortes I dug all of those signals until I was convinced what the target was. I still dig a lot just to convince my self, but also because masking can have a similar effect. With a good target next to a bad target, the meter information will not be as clean. A good example is to sandwich a nickel with a dime. Scan it with the dime side towards the coil, then scan it with the nickel side towards the coil. What would you expect the meter to read? You probably thought what I thought: with nickel up you would get a strong nickel centered reading, or with the dime up a strong dime centered reading. I was surprised to that neither of those things occur. What you get is reading between those two target types, and it doesnt even indicate its a coin. The machine is seeing the conductivity of the "target". Now if you separate those targets a bit, which is common scenario, its a whole different ball game. By careful scanning and altering your sweep and stance, in some cases you can tell there are two separate targets there. This example is only to emphasize that masking of targets can radically alter what you see on the screen, so you need to be aware of that when deciding to dig, or not to dig. If you are primarily a coin hunter, ID has its advantages, it does give you more information, but you must use caution.
