Visual displays simplify our hyperspectral world into three channels (RGB), controlling the activity of cone photoreceptors. Recent data show that a new photoreceptor in the human eye-melanopsin-also contributes to visual perception. Current image capture and display technologies, however, do not account for this new dimension of vision. We have addressed this deficit, and have applied our updated understanding of vision to develop new, biologically relevant methods of image capture, processing and display. Here, we describe a multi-primary display that controls melanopic activity independently of chromaticity and luminance. We have used this device to present images varying in their relative melanopic activity, and have asked naïve participants to judge differences between images. We find that regulating this additional melanopic dimension improves the appearance of images matched in chromaticity and luminance. In sum, including a melanopic dimension could represent a new approach to improving the quality of image capture and displays.