Twenty pairs of photographs were made of adults looking 25° to the left and 25° to the right while attempting to face forwards. The eye regions of each photograph were concealed. Twenty adults attempted to sort each pair into left-looking and right-looking pictures. They were successful 65% of the time, p <0.001. This suggests models have difficulty looking to one side without a perceptible head turn or comparable facial cue. This previously unrecognised phenomenon has implications for research on detection of gaze.