The invention relates to an x-ray device and method for taking an x-ray image of a skull of a person using a cephalostat. The cephalostat (104) comprises a first fixating organ (111) and a second fixating organ(112) for fixating ahead of the person at opposite sides of the head such that a sagital plane is transverse to a direction of an x-ray beam (101A) originating from an x-ray source(101). According to the invention,an outer contour of a shielded area (SA) is defined. The defined shielded area (SA) prevents a head from x-ray radiation and leaves landmarks for diagnostics accessible. The shielded area is valid for a large variety of individuals. Frequent adjustments to a shielding mask are no longer necessary for each individual. The shielded area is obtained by implementing a mask (150, 1) at the cephalostat for blocking a part of the x-ray beam.
