Lens Element Pairs in Small Oval Cases Question

[DanK]

I've seen a few small oval felt lined cases that contain what appears to be the front and rear elements of a lens - couple were Emil Busch branded...

What are these lenses designed for? I've searched and found little to nothing...

Are they made to be set in a barrel, or similar? Or are they designed to be set in a shutter?

If either of the above is the case, how does one go about determining the mounting distance - front to rear - of the elements, if the original barrel or shutter is unknown?

Thanks,
Dan

[Steven Tribe]

Front and rear lens cell sets were sold to owners who have already a shutter. This could be a "wide angle" which could replace the "normal set" which was present in the shutter/camera when new. These sets were sometimes an optical compromise - so people got a sort of wide angle. Sometimes, the thread spacing on the shutter was a perfect match for a known better lens. There was a great deal of development in photographic optics between the start of shutters in the late 1890's and the 1920's and some shutters kept going! Many catalogues (see cameraeccentric) list products and prices:
-in barrel.
-in shutter x or shutter y.
-as cells - to be installed in your shutter x or y.

[DanK]

Thanks Steven,

I appreciate your response.

One of the sets, was a wide angle.

Another vague question - were there standard shutter and barrel dimensions across manufacturers of early lenses, or were each specific to the maker?

I'm curious as to how difficult it will be to find a barrel or shutter for the pair of lenses.

Thanks again,
Dan

[Steven Tribe]

I think the general answer is no. The american shutter and the german shutters had their own sizes. This means, for instance, that the B&L protar XXmm cells will fit in a B&L shutter whilst these cell will not fit in a german shutter which had a Zeiss version of the protar XXmm. It is possible to do a bit of detective work using the many old catalogues available online - if you can identify the the cell pairs. In the tables of various sizes there will be a shutter type(s) noted - usually with size given. There are not so many shutter sizes as focal lengths as the makers wanted to keep things simple! If you are good at measuring thread diameters and pitch - there are lists of the various sizes.

I have seen just about every make/size of shutter listed on e**y through the years. Many of them still work - or can be made to work. Remember that the present Fscale plate matched a particular lens pair, e.g F6.8 for a dagor of 180mm so a new scale would have to be made to match your lens pair.

[DanK]

Thanks again Steven...

I've looked at the literature I could find, and found a little info...thanks for the link as well...

Worst case scenario, I am guessing I could use the cells individually.

I'm still curious if there is a method to determine the proper spacing from front cell to rear cell, if I were to fabricate my own barrel....or is this something you must have documentation with measurements of some sort to determine?

Thanks,
Dan