1. An examination apparatus for examination of an object of interest, the examination apparatus comprising: a radiation source adapted for moving on a scan path around the object of interest and for emitting electromagnetic radiation to the object of interest; a detector unit adapted for detecting image data from the object of interest; a reconstruction unit adapted for reconstructing the image data on the basis of an approximate reconstruction procedure; wherein the examination apparatus is adapted for performing a periodical movement of a focal spot of the emitted electromagnetic radiation in an axial direction during the movement of the radiation source.