Bausch & Lomb lens identification

[Laskadog]

Almost 25 years ago I moved into a house and the previous owner had left a few decorations lying around. One of them was this mysterious optical thing that I had always assumed was part of an old telescope or something. I'm just getting into Wet Plate and the other during a Youtube marathon I had a eureka moment. While watching a photographer set up his antique 8x10 camera his lens looked unbelievably like my mysterious scope. I decided to while the layers of dust off it and found out that it has a Kodak shutter with f-stops and everything. Anyone know what it might be?

The lens has the following engraved on the side: Bausch and Lomb Optical Co., Rochester N.Y. & New York city 58895
Inside the lens Is says Kodak ball bearing shutter, patten info and a date of 1910.

Any help would be appreciated. Google wasn't much help

[Mark Sawyer]

That shutter doesn't belong in that lens barrel. Somebody just randomly stuck it in there. The lens is probably off a vest-pocket folding camera, and the brass barrel is for a magic lantern.

[Laskadog]

That shutter doesn't belong in that lens barrel. Somebody just randomly stuck it in there. The lens is probably off a vest-pocket folding camera, and the brass barrel is for a magic lantern.

Interesting! Thanks Mark So it's some kind of Frankenstein lens. Although there is no actual shutter, just an iris. I'll take a closer look at it. Hopefully it will take nice pictures.

Now I'm wondering how to mount thison a lens board. The goal was to try it out on my Calumet 4x5. The large thread is on the front of the lens.

[Laskadog]

So I had a go at the lens this morning and took it apart. There was some serious DYI job done a very long time ago. After unscrewing all the sections, I got to the stainless barrel part with the Kodak shutter inside. The shutter is screwed into a home made sleeve that inserts into the body of the lens. The sleeve is made out of an old piece of tin from some kind of container. You can still see some of the old labelling in the picture. Not a bad job, but far from perfect.

The Kodak shutter has been butchered, cut, filed down and has some screws missing. All that is really good is the lens. The the iris doesn't really move, so changing the f-stop is not possible. I took that lens apart as well to clean it since it was filthy. It does say Bausch and Lomb on that lens as well, but I assume they made it for Kodak and that it is not original to the projector lens. All very interesting.

My question is now, why? Was this how they converted a projector lens to a camera lens? Without the Kodak shutter lens, there is only one element in the front. Did projector lenses only have a large front element? To be honest, I'm not even sure that the sections are assembled in their original sequence, but I can't see any other way to screw them together.

[Mark Sawyer]

The lens is an f/8 Rapid Rectilinear, pretty dim for a projector lens, but it could have been used that way. Projection and taking lenses are very similar, (many of us use Magic Lantern or other projection lenses on our lf cameras), so the original lens configuration in that brass barrel would have been fine for either. You could perhaps measure the barrel and find some cheap diopters to make a periscopic lens and use it, sell it cheap for parts, or just keep it as a souvenir...

[Laskadog]

I guess that is what the original DYI was going for. Not sure it will take decent pictures, but I might try to mount it anyways and see. Thanks again Mark, you have an impressive knowledge of the subject

[Lee Rust]

The lens barrel and focussing screw look very much like the telescope on my grandfathers survey transit, which was made around 1901.

[Laskadog]

Mark, May I impose upon you for a little more of your know how? I'm reading like a sponge, but it's slow going and I've yet to find a single picture of my exact lens for comparison. You're saying the magic lantern lenses only have the one front element? If I remove the kodak lens, I can use just the magic lantern lens with the single front element or does it need that Kodak lens to work on a 4x5?

You mentioned Diopter lenses. What would be the advantage of that? Are those for close-up photography?

Thanks,

[Mark Sawyer]

Lenses of this sort were usually Petzvals or Cooke Triplets. If the front element you have is really the original front element, it will be either a cemented doublet (Petzval) or a single element (Cooke). Both design would have two single elements towards the rear. Google them for the layout, but either way, you're missing a couple of elements.

Yes, the diopters are the magnifying "filters" you screw on the front of a regular lens to shorten the focal length or use it as a macro. If you put a +2 facing outward at each end, that would give you about a 250mm Periscopic lens, fairly sharp in the middle but soft at the corners. You'd have to find the right size and figure how to mount them in the barrel, but they're cheap and easy-to-find in many sizes on ebay. You could also use one in conjunction with the existing front element, if it's a positive (magnifying) lens.

[Laskadog]

This thing just keeps getting weirder. The front element is a 2" Plano-concave lens (flat on one side and concave on the other). It seems more to be the centre element of a Cooke lens. This would make sense since the unit it is housed in has threads on both sides. I fear there is simply too much missing from this lens to make something out of it.