A method for evaluating a specimen, the method can include positioning an energy dispersive X-ray (EDX) detector at a first position; scanning a flat surface of the specimen by a charged particle beam that exits from a charged particle beam optics tip and propagates through an aperture of an EDX detector tip; detecting, by the EDX detector, x-ray photons emitted from the flat surface as a result of the scanning of the flat surface with the charged particle beam; after a completion of the scanning of the flat surface, positioning the EDX detector at a second position in which a distance between the EDX detector tip and a plane of the flat surface exceeds a distance between the plane of the flat surface and the charged particle beam optics tip; and wherein a projection of the EDX detector on the plane of the flat surface virtually falls on the flat surface when the EDX detector is positioned at the first position and when the EDX detector is positioned at the second position.