Which Kiron lens in particular are you looking at? Kiron was indeed, founded by sone top Nikon lens designers. They are very good, and built as well or better than the Nikon's. As other's have stated, Kiron (Kino Precision Industries) did make many of the older and superb Vivitar Series 1 lenses. Kiron made an excellent 24mm f/2 and a 28mm f/2. The Kiron 105mm f/2.8 macro, is phenomenal, and goes 1:1 life size without any adapters. I also use the excellent Kiron 28-105 and the Kiron 70-210. Join the Kiron Klub ( http://groups.yahoo.com/group/Kiron-Klub/ ) and you'll have access to loads of info on any Kirons or Vivitars.