What kind of lens is this??

[John Kasaian]

I unscrewed these unmarked lens elements off a No.5 Universal and I'm curious as to what type or design it represents. The scale on the shutter was completely off, so I don't know which f/stop it starts with---or else I'd have taken a picture with it just to see if I liked the results. The elements are symmetrical on both sides of the stop, so I'l only describe one side. The first element facing the stop is concaved on the stop side and convexed in verso, then theres a spacer with the second element being air spaced with a plano and the "outside" being convexed like a meniscus. None of the elements are cemented. The same configuration is on the other side of the stop. I can't find an example in Kingslake's book. Does anyone have any idea what this might be? Thanks!

[Steve Hamley]

John,

Looking through the lens diagrams in the Lens Collector's Vade Mecum, I'd guess that the outside element is really a bit concave on the inside surface and the design is some kind of a wide field Gauss. Is the shutter Kodak branded?

Of course, if either of the elements is a cemented doublet or more, more possibilities exist. Are there any ghost reflections?

Steve

[Neal Shields]

I have a book called Photographic Principles and practice by Neblette published in 1938. If I understand your description correctly it has a diagram like that which is identified as a:

Cooke Series VIIb. (Wide angle)

It is said to cover 90 degrees at F16 and 100 at F32

It says it is based on a Gauss design

It also has a Dallmeyer F11 variation.

[John Kasaian]

Steve, no ghost reflections. Neal, Thats it! Its puzzeling that whoever owned this lens went to alot of expense to have adapters machined to fit a shutter, but didn't bother with a f/stop scale.

Thank you.