Red Robin
It Is What It Is
wondered if this might be a good choice on a leica iiif?
Ironically, my first I-10 (Fed50) was a late coated example and worked great.
Condition is everything, but at 15-20$ a pop, find a dealer on eBay and buy as many of their stock as you can, save on combined shipping! Not a bad route, get 4 or 5 to pick through, return or sell the rest. I'm sure Fedka would give you a 5$ return on a complete lens, if not adorama.
I just tried the I-22 on my IIIF body and found it doesn't focus accurately at 1 meter.
To test rangefinders, I measure 1 meter from the film plane and place a focus target. If the rangefinder and lens combination doesn't show that it is correctly focused at that distance, there is a problem either with the indicated distance on the lens or the rangefinder setup. On the Fed 2, the I-22 showed correct focus at 1 meter, and photo tests have verified that. The same lens put on the IIIF showed a RF focus distance of 1.1 meters approx, so it would be out of focus unless well stopped down. I may do some film tests later, but it seems likely to be a problem close-up, with decreasing amounts of error at longer distances.