A method and a system for influencing an optical output of image data on an output device in a vehicle. A viewing direction of a driver of the vehicle is determined. If the determined viewing direction is directed to the output device, the optical output of the image data is faded down with an average fading out rate DOWN. The fading out rate DOWN defines a temporal decrease in the optical perceptibility of the output image data by a human. If the determined viewing direction is directed towards the output device and is directed away from the output device, the optical output of the image data is faded up with an average fading in rate UP. The fading in rate UP defines a temporal increase of the optical perceptibility of the output image data by a human.