A method for imaging a material to atomic scale by means of a field-ion microscope having a vacuum chamber configured to accommodate the material prepared in the form of a tip and an imaging gas, and an ion detector is provided. The method includes application of a DC electrical potential (VDC) and of a pulsed electrical potential, of which the maximum pulse value is denoted Vimp, so that the tip erodes for a potential value equal to VDC+Vimp; acquisition, by the detector between at least two pulses of the pulsed potential, of series of at least two ion images of the impacts of the ions repelled by the tip onto the detector; and calculation of a quantity characteristic of a trend of the erosion of the tip based on the series of ion images acquired and the adjustment, between each series of images, of the values of VDC and of Vimp such that the quantity characteristic of the trend and the ratio VDC/Vimp remain constant.