Quote Originally Posted by John Layton View Post
...so if I were in the market for a 450mm Fujinon-C, but my current needs were for 5x7, then I might be at least equally well served by a 19" Red Dot Artar?
As a bit of trivia as much as anything else, Goerz made a 450mm Red Dot Artar. In their literature they refer to it as a 17 3/4 inch/450mm lens. Oddly enough the few examples I've seen (three, all on ebay) were engraved "45 cm" rather than the usual marking of the focal length in inches. In a shutter these, like the 19 inch RDA, will be in a No. 4 Acme so maybe not as desirable as the 450 mm Fujinon-C's No. 1 Copal. I have a No. 3 and and a No. 4 Acme. Their fastest speeds are, shall we say, aspirational but the speeds do test out as consistent.

David