1. A method of representing a virtual object in a view of a real environment, comprising: a) providing image information of a first image of at least part of a human face captured by a first camera; b) providing at least one human face specific characteristic, wherein the at least one human face specific characteristic comprises a radiance transfer property of at least part of a face; c) determining at least part of an image area of the face in the first image as a face region of the first image; d) determining at least one first light falling on the face according to the face region of the first image and the at least one human face specific characteristic; e) blending in the virtual object on a display device in the view of the real environment according to the at least one first light; wherein the step d) comprises steps d1)-d4); d1) providing a plurality of face sample positions; d2) providing, for each of the plurality of face sample positions, a radiance transfer function; d3) determining image positions of at least part of the face sample positions in the first image; and d4) determining the at least one first light according to intensity information associated with the image positions of at least part of the face sample positions in the first image and the radiance transfer functions associated with the at least part of the face sample positions in the first image; wherein the radiance transfer functions are determined according to a training method comprising: f1) providing image information of a plurality of images of human faces in a plurality of different illuminations, wherein the plurality of different illuminations are known; f2) determining, for each of the plurality of images, image positions of at least part of the face sample positions; and f3) determining, for each of the plurality of face sample positions, the respective radiance transfer function according to intensity information associated with the image positions in at least part of the plurality of images and the illuminations and poses associated with the at least part of the plurality of images.