1. A method of removing an object from a CT image comprising the steps of exposing a body to radiation at a plurality of angles about the body, detecting radiation passing through the body at the plurality of angles to create a projection set made up of a plurality of projections each made up of a plurality of elements, defining in an unmodified projection set a rub-out region encompassing the object to be removed, operating on the elements in the projection set to determine average densities for each element of each projection within the rub-out region and slightly beyond by combining associated elements from neighboring projections, estimating from the average densities just outside the rub-out region what the densities within the rub-out region would have been if the object were not present, combining the estimate and the average densities to create a rub-out signature, producing a modified projection set by combining the rub-out signature with the original projection set to remove the signature, and producing a corrected image from the modified projection set.