Method for controlling a headlight system (145, 150) of a vehicle, having the following steps: - reading in image information of an image from a camera; - providing a colour indicator value for at least one partial detail of the image from the camera, wherein the colour indicator value represents a ratio between a first parameter and a second parameter, wherein the first parameter represents a value obtained by applying a first colour filter to the image information in the partial detail and the second parameter represents a value obtained without applying a colour filter or by applying a second colour filter, which is different from the first colour filter, to the image information in the partial detail and wherein the provision step entails a gradient indicator value being provided that represents a brightness difference, extractable from the image information, for the different, in particular adjacent, image areas of the image from the camera; - determining an aerosol intensity value by using the colour indicator value in order to determine and provide an intensity of the aerosol in the field of view of the camera of the vehicle as an aerosol signal (140, 297), wherein the intensity of an aerosol represents a quantity of drops or particles that appears to be present in the field of view of the camera of the vehicle and wherein the determination step entails the aerosol intensity value being determined by using the colour indicator value and by using the gradient indicator value; - reading in the aerosol signal (140, 297) representing a detected intensity of the aerosol in a field of view of the camera of the vehicle; and - controlling (420 - 460) an alteration of an emission of light in a lighting area in; front of the vehicle by the headlight system (145, 150), in response to the aerosol signal; characterized in that the determination step, before the determination of the aerosol intensity value, entails the colour indicator value being normalized in an area between colour indicator limit values and the gradient indicator value being normalized in an area between gradient indicator limit values and in that further a step of detection of the presence of an intensity of the aerosol critical for road traffic in the field of view of the camera of the vehicle is provided if the aerosol intensity value is in a predetermined relationship with a threshold value. - reading in image information of an image from a camera; - providing a colour indicator value for at least one partial detail of the image from the camera, wherein the colour indicator value represents a ratio between a first parameter and a second parameter, wherein the first parameter represents a value obtained by applying a first colour filter to the image information in the partial detail and the second parameter represents a value obtained without applying a colour filter or by applying a second colour filter, which is different from the first colour filter, to the image information in the partial detail and wherein the provision step entails a gradient indicator value being provided that represents a brightness difference, extractable from the image information, for the different, in particular adjacent, image areas of the image from the camera; - determining an aerosol intensity value by using the colour indicator value in order to determine and provide an intensity of the aerosol in the field of view of the camera of the vehicle as an aerosol signal (140, 297), wherein the intensity of an aerosol represents a quantity of drops or particles that appears to be present in the field of view of the camera of the vehicle and wherein the determination step entails the aerosol intensity value being determined by using the colour indicator value and by using the gradient indicator value; - reading in the aerosol signal (140, 297) representing a detected intensity of the aerosol in a field of view of the camera of the vehicle; and - controlling (420 - 460) an alteration of an emission of light in a lighting area in; front of the vehicle by the headlight system (145, 150), in response to the aerosol signal;