What did I buy?

[DrTang]

camera show yesterday..found a lens that seemed like a good price.

I'm figuring it's a military issue enlarging or process lens... but I don't see a match in my searches

Wollensak 304mm f5.6, W in a circle, mounted in a brass fitting that is army olive drab in color

no back element, apeture blades behind the front cell(s)

your guess?

http://www.mericphoto.com/stuff/weirdlens.jpg

[Lachlan 717]

Does it produce an image?

[DrTang]

Does it produce an image?

looks great on a GG..covers 8x10 indoors anyway

[Geoffrey_5995]

w in circle means Wo Coated meaning it was a Wollensack coated lens. This lens does look military and reminds me of the Goerz 304mm f5 single achromat lens. This lens is often referred to as a special portrait lend shoots beautifully as a soft focus portrait lens but I believe it was for military use on a tank. I have a few of these and one has a red stamp with some numbers and symbols that look military.

[Dan Fromm]

How many groups and elements does it have? Count reflections, and remember that dim reflections from glass-cement-glass interfaces can be very hard to see.

From a great distance, and remember that I have a cold and am temporarily nose dead, it smells like the front cell of a telephoto lens. I think I recall discussions of 12"/5.6 Wolly teles.

Against that, it isn't clear that the rear of the barrel is threaded to accept a rear cell. Is it?

[DrTang]

the rear isn't threaded and the tele's say 'telephoto' on them.. but in a military issue - who knows

looks like there is two reflections besides the one off the front surface of the lens

[Dan Fromm]

Well, if there are two strong reflections and one weak then the group is a cemented doublet. So is the front half of a classic telephoto lens, but that proves nothing.

That the rear isn't threaded suggests that you might have an achromatic doublet. If so, the back focus will equal the focal length. Does it?