Need help B&L Lenses

[einman]

So I purchased a B&L SZ7 which came in an original wooden storage box. In the box there were 4 lenses 2 10x and 2 15x. They occupied slots obviously made specific for the lenses. They have threads on one end. I have never seen anything like these before. I'm guessing because there were 2 each, they are eyepieces of some sort. Anyone familiar with these lenses?

[PeteM]

Those are new to me. But I have seen a few different eyepieces with threads at the top; meant to attach eye guards.

[einman]

Those are new to me. But I have seen a few different eyepieces with threads at the top; meant to attach eye guards.

Yes, so have I. However, these are 33mm in diameter. I have not tried yet to see if they will screw in place of the original focusable eye tubes. Just a thought. Though I do not know why you would even want to do that.

They are obviously quality optics. As in Jurassic park - "Are they heavy?" then they are expensive.

The scope also came with auxillary objectives intended for the lower model SZ's as well as a 2x objective for the SZ7.

[Scarodactyl]

Just some random eyepieces. Not sure who used 33mm ones, some sort of dinosaur for sure.

[apochronaut]

Could you show the optical ends?

[einman]

Could you show the optical ends?

Threaded end

Threaded end up close

[apochronaut]

So, they do look like eyepieces with the field stop evident. Perhaps the extra 33mm diameter is because they are a fairly simple design and it was a way of getting a reasonably wide field . That was the case years ago and why stereos have larger oculars.
The threading might be due to their use, which might have been communal. Eyepieces might not go missing if threaded in tight.

[Scarodactyl]

I am pretty sure those would have accepted eyecups, which might have been lost or cracked.

[einman]

Hmmm..what is puzzling is why they were in the wooden case with a B&L SZ7. Perhaps for lack of another storage area. There was also a 1x and a 2X threaded objective. I am guessing for the SZ1-4 microscopes. Although the diameter seems a bit large for that. Given I have never owned a B&L sz1-4 I am guessing. They are black and do not look like the 2x lens on E-bay.

[Scarodactyl]

Show pics please.
This sort of mix and match happens all the time in lans. Stuff is always getting moved and consolidated.

[einman]

This is the 2x. Both lenses are 62 mm in diameter

[apochronaut]

I suspect the lot are from a different system. B & L had a lot of stuff going on outside the consumer market. There wss the photo reconnaisance stuff for one, which were all modified stereozooms. The 75, 95 the Z250 and others, some of them required to achieve really high magnification and wide field.
Your parts could be from one of those. While B & L had committed to 23mm tube for the aforementioned and that did not impinge upon their field aspirations for a 15X eyepiece, there are physical restrictions to a wider field at 10X, so those eyepieces could have been transitional types, before the 15X U.W.F. was introduced. It didn't exist for the 75, 95 or other forensic scopes and was introduced for the Z240. There are fitted cells for a pair in the Z240 case and therr werr no 10X equivalent. The 10X have exactly the same field coverage as the 15's, although the 10X have an added modification of a laterally orbital eyelens which majes them self collimating.

[einman]

Apochromat- I acquired the SZ7 from an electronics company. It is quite possible the lenses were from another application as you suggest. At this point they are just paperweights.

[Scarodactyl]

None of these are b&l. The recon system did have special aux lenses but they are all branded and don't look like this. The special 2x has a long snoot, presumably to make it parfocal since it had an objective slider.

[apochronaut]

The model 95 used a pair of 2X supplemental lenses mounted below the rhomboid arms to double the magnification but I haven't seen them. The 95 rhomboid arms also had lenses fitted into a prism housing but the supplemental lens threaded on, so would have a circular housing but not likely of 62mm.
B & L didn't brand everything, especially for industrial stuff and they changed that over time too but I agree, they don't look to be B & L.
However, the early photogrammetric pods had very large ports into the head. The eyepiece tube has to flare into a cone in order to fit the port, as though originally the design incorporated a much larger eyepiece tube in order to get the wide field, then as they adopted more advanced designs of W.F. eyepieces, using those made more sense and 23mm became the tube size. I can't figure out why the ports would be so large, otherwise. This is pre-1965.

[Scarodactyl]

I have one of the heads with the gigantic looking eyetubes. Very odd design, and unfortunately thoroughly molded. Iirc there are a lot of prisms in that head, I'll have to pull it off the shelf and have a look.

[apochronaut]

By far the most common one is the Z240 but there were 4 others that I know of. The Zoom 70 which views ip to 70mm film, the Zoom 95, which views up to 9 1/2" film, the Versatile which incorporates higher magnification, and the Z400 ( maybe 500). The earlier two had convergent eyetubes, the last three parallel eyetubes in order to provide less overlap and more space for the mirror system.
The earlier Zoom 70 had a mirror porro head but in order to improve imaging and provide optical image rotation the later 70 and all the others used a combination of 3 prisms to get an even number of reflections. A dove prism, a pechan prism and an amici roof prism, that's why so many prisms.

Prior to the introduction of the Versatile, they used a bridged pair of Dynazooms for high magnification imaging of aerial photos. The project was headed up by James Benford, I think.