A method for determining an orientation in space of a substantially cylindrical shaped elementary object using a radiography device comprising a source of X-rays and a detector disposed opposite the source is provided. The radiography device is arranged to record a projection image of the elementary object when the elementary object is located between the source and the detector. The method includes: determining a quantity A of X-rays absorbed by the elementary object on the projection image and evaluating the sine of an angle theta as a function of the quantity A of absorbed X-rays, wherein the angle theta is between a longitudinal axis of the elementary object and a plane of the projection image.