This bad boy was of course Voigtlander's answer to the Goerz Dagor. I've not seen another like it. The somewhat smaller Series III is a bit more common I suppose. This was the flagship lens. Look at the chart and you will see that the 17" #8 can cover a 16X20 plate at f32. I never got to use it, and now I am divesting myself of some of the giants. I never had a flange for it. Glass is beautiful and aperture is smooth. It's ready to populate the real estate on your 12X20 or 14X17. It's heavy! I think it's worth $1025.00 That's what a ULF Goerz goes for and this is far more interesting.