A holographic method with numerical reconstruction for obtaining an image of a three-dimensional object, employs a digitalized hologram of an object or of a portion thereof, and includes starting from the digitalized hologram, extracting a phase image of the object corresponding to a matrix MD of distance values, selecting a subassembly SD of the distance value assembly present in matrix MD, subassembly SD containing distance values dk, extracting from matrix MD an iso-level assembly IQdk of corresponding bidimensional …