An imaging apparatus includes a media support surface. A light source and a light detector are positioned in relation to a reflective surface such that when a sheet of print media covers the reflective surface, a reflected specular light component of a light beam is received by the light detector, and when the reflective surface is not covered, the reflective surface directs the reflected specular light component of the light beam away from the detector. The signal strength of the output from the light detector when receiving a diffuse light component reflected from the reflective surface is less than the signal strength of the output from the light detector when receiving the reflected specular light component that is reflected from a low reflectance print media.
