A capacitive imaging method or device using an array of row electrodes 101 and column electrodes 102 on a substrate 100, wherein cross-capacitance between row and column electrodes is obtained from row electrode 101 self-capacitance measured with the remaining electrodes grounded, column electrode 102 self-capacitance measured with the remaining electrodes grounded, and combined row and column electrode self-capacitance measured with the remaining electrodes grounded. A preferred embodiment is a hand-held wall scanner for detecting hidden features having a two-dimensional display the size of the array and located over it. Hidden features influencing row-to-column cross-capacitances are thus imaged in real size and at their real location.