1. A calibration method for at least one projection apparatus for projecting images onto at least one projection area, wherein the at least one projection area is associated with geometric data having been or being stored in advance in a computer unit, comprising: a) projecting, with the at least one projection apparatus, previously known calibration patterns onto at least a portion of the at least one projection area, b) recording the previously known calibration patterns by at least one camera apparatus as a calibration image, wherein data of the calibration image is transmitted to the computer unit, c) automatically determining, by means of the computer unit, a deviation between the recorded calibration image and an ideal imaging result of the previously known calibration patterns on the at least one projection area, the ideal imaging result forming a reference pattern, wherein an actual arrangement of the at least one projection area, of the at least one projection apparatus, and of the camera apparatus is modeled in a virtual three-dimensional model according to known geometric data of the at least one projection area, of the at least one projection apparatus, and of the camera apparatus, and d) determining, by means of the computer unit, a correction transform from the deviation between the recorded calibration image and the reference pattern such that a transformation of a real projection of images by means of the correction transform by the at least one projection apparatus corresponds, particularly in an overlap region, with the reference pattern apart from a minimum deviation, wherein the correction transform causes a displacement of at least one point of the recorded calibration image onto a point of the reference pattern.