1. A method for determining a registration error of a feature on a mask, comprising: providing a first aerial image that was captured by means of a position measuring device and includes at least said feature, simulating, from pattern specifications of the mask, a second aerial image that includes at least said feature, taking into account at least one effect that causes distortion of said first aerial image, and determining the registration error of said feature as the distance of the position of said feature in said first aerial image from the position of said feature in said second aerial image.