Glass (photographic lens)
A colloquial term, “Glass” is used to describe a photographic lens. It is used as a descriptive term by photographers who appreciate the quality of a lens and the part it plays in the camera/lens system. The quality of the “glass” is probably the most important component of the photographic process – a photographic lens or camera lens is often considered more important than the camera that it is mounted on. References to the quality of the “glass” are statements about the photographic quality of the photographic lens.