Rare Early Wollensak Professional 6\" F4 Cine-Telephoto for 16mm C-Mount c.1930s For Sale

6\" F4 Wollensak Cine-Telephoto

Hello and thanks for looking. Early Wollensak 6” F4 Cine-Telephoto serial #4951 in C-mount which dates it to the early 1930s per a quick internet search. Includes what appear to be its original caps. Barrel shows age as you might expect for something nearly 100 years old. Glass is very good with some internal dust and fine wipe marks but nothing serious. Focus is smooth and the diaphragm is clean and turns freely. Not a lens seen often or maybe at all. I can’t find another example online. Everything you see is an F4.5 (either Cine-Telephoto) or the F4.5 Raptar but F4, as this one is clearly marked, is not to be found. And because of that I did some further internet sleuthing (basically asking AI, then refining the questions) and it appears that this lens was part of Wollensaks early push into professional 16mm film making that was happening when B&H Filmos and Bolex 16mm cameras entered the market. One of the key indicators is that it’s F4, not F4.5. Every 1/2 stop counts especially back then. The second and more defining indicator is that it focuses down to 4 ft. Instead of trying to summarize what Google’s AI said to me I’ve included a few screenshots regarding the close focus distance and PAT APPL’D for marking. I found it an interesting read. But I still haven’t found another example of this lens so it seems to be a rare bird indeed.