title: Authors' reply.
abstract: This reply clarifies that it is possible to change the plane of cut by filtering a tomogram, if the presence of the out-of-focus images is tolerated, because the (projected) images of all the layers are superimposed on the film and any filtering will process all these images simultaneously.
authors.forename: J M
authors.initials: JM
authors.lastname: Costa
authors.forename: A N
authors.initials: AN
authors.lastname: Venetsanopoulos
authors.forename: M
authors.initials: M
authors.lastname: Trefler