1. An imaging system comprising: a light guide having: a first surface capable of receiving ambient light; and a light-output surface; an image sensor disposed along the light-output surface of the light guide; and light-turning features forming a plurality of light-turning pixels disposed on the first surface of the light guide, wherein the plurality of light-turning pixels are capable of selectively capturing the ambient light incident on the pixels within a range of acceptance angles and directing the selectively captured ambient light towards the image sensor, and wherein at least some of the light-turning pixels have ranges of acceptance angles different from others of the light-turning pixels.