I took a risk and bought a bigger lens on eBay. I'm hoping you guys can help me figure out what optical formula of lens it is. I have no experience trying to decipher this from looking at a lens so I snapped some bad cell phone pics as the mail lady dropped it off. The lens is marked "18in E.F." on the barrel. The holder for the lens is marked "Bausch & Lomb Optical Co. Rochester, N.Y. U.S.A. 1327". I think at some point in the past there was a rack and pinion setup to allow the lens barrel to be focused relative to the holder. I assume this implies it was once a projection lens.
The optical barrel is black along the entire length. The front group separates on threads from the main barrel and the rear group. NOTE: for the whole thing, I'm making the assumption that the "front" group is the one on the left in this picture since it has more glass in it.
What I'm assuming is the front group appears to have either 2 or 3 elements in it. Here's the front group shot from the front/outside:
Here's the front group shot from the rear/inside:
Split because of image rules...
Bookmarks