Standoff Distance

The gap between the probe tip and the accessory surface during measurement, in centimeters. Magnetic field strength falls off rapidly with distance, so the standoff must be consistent across all measurement points to make readings comparable. For discs and pancakes, place the probe directly on the surface (0 cm standoff). For loops, hold the probe at the middle of the accessory's height along an even horizontal plane; that midpoint is the z=0 reference every depth plane is measured from, and it applies whether the loop is round tubing or a flat band. See Z-Axis.