When posing for a portrait people tend to offer the left cheek; however self-portraits typically depict right cheek poses. Why? If the right cheek bias for self-portraits results from artists offering their left cheeks to a mirror, then right cheek self-portraits should become increasingly infrequent following the introduction of affordable cameras. The present study was thus designed to determine whether orientation changed as a function of the date of composition by examining 1193 self-portraits from 24 international galleries. Self-portraits were split into seven groups by date: Group 1 Pre-camera: 1452-1539 (N=25); Group 2 Pre-camera: 1540-1639 (N=65); Group 3 Pre-camera: 1640-1739 (N=61); Group 4 Pre-camera: 1740-1839 (N=141); Group 5 Early cameras: 1840-1887 (N=235); Group 6 Kodak cameras: 1888-1935 (N=411); and Group 7 Cameras popularly adopted: 1936-2008 (N=255). Consistent with prediction, results confirmed that the right cheek bias in self-portraits changed over time, from 61.6% of pre-camera portraits (1452-1839), to 43.2% of post-camera portraits (1840-2008). Although the decrease in right cheek pose frequency did correspond with an increase in left cheek poses (1452-1839 mean 32.9% vs 1840-2008 mean 39.8%), the greatest proportional change since the introduction of the camera was the frequency of midline poses, climbing from 4% of 1452-1539 portraits, to 31.5% of 1936-2008 portraits. Thus these data imply that the availability of affordable cameras might have influenced self-portrait posing biases.