Method and x-ray computer tomograph for analyzing an object by means of x-ray computer tomography

In a method and an X-ray computer tomograph (1) for analyzing an object (2) by means of X-ray computer tomography, object-projection data sets are determined for a plurality of projection directions, and from said sets associated irradiation length data sets are calculated by means of a processing unit (11). The irradiation length data sets comprise the length of the object (2) irradiated by the X-ray radiation (6) for each projection direction and for each pixel (p). From the irradiation length data sets, associated reference projection data sets are calculated by means of the processing unit (11), said sets comprising information about virtual object errors (13). By means of the processing unit (11), the object projection data sets and the calculated reference project data sets are evaluated such that virtual object errors (13) and real object errors (13) can be differentiated individually in the object to be analyzed (2).