Cone and melanopsin contributions to human brightness estimation: comment.

A recent study of large-field subjective brightness perception under different narrowband spectra and different luminances revealed distinct contributions of cone photoreceptors and intrinsically photosensitive retinal ganglion cells containing the photopigment melanopsin. The data from this study were analyzed with a recently published model of spectral sensitivity for full-field brightness incorporating three primary channels: a luminance (achromatic) channel, a blue-yellow opponent color channel, and a melanopsin channel. There was good agreement between predictions based on this model and the recently published brightness perception data.