	Unlike most of the other manufacturers involved in 35mm camera production, the Nikon F was released with a full range of lenses from 21 mm to 1000 mm focal length. Nikon was also among the first to introduce what is commonly known today as 'mirror lenses' – lenses with Catadioptric system designs, which allowed the light path to be folded and thus yielded lens designs that were more compact than the standard telephoto designs. Subsequent top-of-the-line Nikon models carried on the F series, which has reached the F6 (although this camera has a fixed pentaprism). With the introduction and continued improvements being made in digital photography, the Nikon F6 is likely to be the last of the flagship Nikon F-line film SLRs.