An aerial image is generated by imaging an object with the use of an imaging optic, the object being illuminated by an illuminating optic by using a light source emitting illuminating radiation, the illuminating optic having a pupil plane. A first data set is defined to represent the object, a second data set is defined to represent the intensity distribution of the illuminating radiation in the pupil plane of the light source, and the aerial image is calculated from the first and the second data set, in which the resolution of the second data set varies according to the intensity or according to the location of the pupil plane. A microscope includes an imaging optic for imaging an object, a detector for capturing an aerial image of the object, and a processing unit for simulating aerial images generated by the microscope.