Abstract: A gaze tracking model is adapted to predict a gaze ray using an image of the eye. The model is trained using training data which comprises a first image of an eye, reference gaze data indicating a gaze point towards which the eye was gazing when the first image was captured, and images of an eye captured by first and second cameras at a point in time. The training comprises forming a distance between the gaze point and a gaze ray predicted by the model using the first image, forming a consistency measure based on a gaze ray predicted by the model using the image captured by the first camera and a gaze ray predicted by the model using the image captured by the second camera, forming an objective function based on at least the formed distance and the consistency measure, and training the model using the objective function.