Räuber
Well-known
Yes, the first 3M serial batch (batch 72) is full of hacked Sonnars and Sonnars made from wartime or pre-war parts. Looking into the table I see more of those hacked Sonnars then legit 3M Sonnars. It really paints a picture of the turmoil that was happening through the dismantling of the Jena production happening at that time. The Soviets took all machines, tools, parts and unfinished lenses from the Sonnar production at the other hand they demanded that Jena should not stop production yet and keep putting out the precious lenses and cameras until the Kiev and Krasnogorsk production is up and running. For Jena this was an unpredictable situation. From one day to the other the Soviets went from "we want you to produce lenses and cameras and we pay you" to "we will take everything to the Soviet union and you need to help us". Some Jena stuffers might have hidden tools and lens parts before the Soviets had the chance to take them. Resuming the production they needed to get their hands on optics and parts and so they resort to spared parts and optics to fill the gabs. Batch 73 looks clean. So they handled this situation very solid.
You will find that changes such as the unmarked F16 aperture came in over time, and samples of each were intermixed as parts were used up.
Now: for the haze. Have you removed the front element to clean from both sides? Haze should come off readily. If you've removed the front element, I would like to see pictures of it held up against a light. These lenses also get a "Bloom" which might look like haze, but it is not and should be left on the lens. If it is haze or worse, the image of just the front element will help determine the problem. If it is not coming off, the glass has etched. In this case, the front element must be replaced. 90 years after the lens was made, this means finding a donor lens. The Sonnar is a "very forgiving design". A front element from another v3 is best, but you can substitute one from an early J-3. It just works.
Räuber
Well-known
@Alberto G That Zeiss secretly changed the aperture when changing from body v3b ZJ CR cd to v3b ZJ CR cb was a theory of me. Seems it is already proven wrong. Your Sonnar is from batch 36. I have 2 Sonnars from batch 37 that have this new modification of the aperture. Looks like Zeiss introduced this change fluently and it has nothing to do with the body. Thank you for posting your finding. Every correction paints a cleaner image of the fuzzy history of the Sonnar 5cm.
Now you need to get you started on Nikkors! (Humor, compliment, mean it!)
simonOWO
Member
Are the optical designs of different Sonnar versions available somewhere? (Curvature, glass dimension and parameters etc)
I can find some very old patent from Zeiss, but the numbers were unreadable, and seems to be the first version only.
I can find some very old patent from Zeiss, but the numbers were unreadable, and seems to be the first version only.
Räuber
Well-known
I wish I could point to an online resource or a book or something. But to my knowledge it is not available. The link to Marco Cavinas page shows some pages from the paperclip documents. But unfortunately the available paperclip pages are incomplete and mostly the quality is not great. I looked through them and almost all calculations that went into production are missing. They are not missing because of the incomplete scan. It seems they were already missing when Merte started sorting and revise the whole collection of papers from Zeiss Jena. There are multiple indexes of all the pages in the document and even if you look into the Sonnar section you will notice that there are not many Sonnar 5cm f/1,5 computations with 7 elements in 3 groups in there. If you can manage to find the pages you will see that they are missing the dates too. The same is true for the Sonnar 5cm f/2. At least the v1 of the f2 with the correct date can be found in there (Zeiss No. 953 / Paperclip ID 626, 627, 628).
For the moment we can only measure and document those data all by ourself. But we have just begone. To get this data we would need to disassemble Sonnar lenses, split the glued glass elements in all parts and measure them with opto scientific precision. For the sake of knowledge I would be willing to sacrifice some of my lenses but I could not do the the work.
@rauber - that would also require a refractometer in order to measure the refractive index of the glass. Measuring diameter of glass and the curvature- "within reason" using hand tools like calipers and Radius gauge, a matter of time. My real optical engineers, Bernie and Bob- both passed away now, where great at reverse engineering optics.
simonOWO
Member
I knew some person with a laser interferometer can measure the curvature. But not refractive index and Abbe number. Do we have some good way to get this done? Measuring the glass properties?
of course If we knew the exact types of glass used in Sonnar versions, we only need the curvature... I think?
of course If we knew the exact types of glass used in Sonnar versions, we only need the curvature... I think?
My optical engineers used an "Abbe Refractometer". This device used index matching oils of different refraction. You compared the glass under test with a mixture of oils. This was a long time ago, I never used it. This would be required as different batches of glass, made by different manufactures can be different. Everyone has their trade secrets. Non could hide them from Bob and Bernie. It was like having TWO Mr Sciences in the Lab.
simonOWO
Member
I notice one of mine v5b sotH and one of mine v5b CR bz have different rear triplet. sotH is longer than the other one.
They shouldn’t if they have the same optical design, if I understand correctly?
I don’t have a caliper to measure the exact length of the triplet.
could it be bad repair with inappropriate parts from other lenses 😡
They shouldn’t if they have the same optical design, if I understand correctly?
I don’t have a caliper to measure the exact length of the triplet.
could it be bad repair with inappropriate parts from other lenses 😡
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boojum
Ignoble Miscreant
It's fun playing ball in the major leagues. ;o)
Räuber
Well-known
I'm no expert of optics but I don't think that you have an inpropriate rear lens element. Probably Zeiss changed the rear element for all Sonnar 50 1.5 and we haven't noticed it yet. Brian might have seen this kind of rear element or some others here too. There is only one optical design change known for the Opton Sonnar. It is not like we have detailed documents about lens production of Zeiss Oberkochen anyway. The only source we have is the Fabrikationsbuch III from Mr. Thiele and it is unknown where he got his information about lens designs from.
At the other hand through other examples I know that the form and size of the lens elements can change but without a new optical formula noted in the production cards of Zeiss. Take the 3M change for example. After WWII CZJ introduced a totally new body with a totally different cut of the lens elements. Brian might confirm that you can not put wartime lens elements into post-war CZJ bodies and visa vis. But the CZJ production cards note the same date of the optical design during wartime and post-war. So Jena did not compute a new optical design but the form and size of those glass elements changed heavily. That suggests that you can change the form and still comply to the lens design calculated by Bertele.
For the post-war CZJ 5cm F1.5 Sonnar: the rear triplet has a smaller diameter, meaning "truncated" a bit- uses less glass, maybe a reduced image circle. I have a couple of transition 5cm F1.5 Sonnars that use the same rear triplet as the post-war lenses, but otherwise look like the wartime lenses. The fixture for the smaller diameter triplet fits into a standard wartime Sonnar.
simonOWO
Member
I understand and have seen different diameters of rear triplet from post-war ZO/CZ. But deviation in length/height (which means light path must've been different as well) should indicate an optical design change. I wonder, if you can confirm this observation with your units, if you happened to have those lens variations? (post war ZO/CZ v5b sotH and later ones)
If so, we might have one more optical design? Or maybe ZO was producing some v4 lenses on the earlier batch?
The post-war West German Sonnar 50/1.5: I've seen different versions with close SN, indicating concurrent manufacture. The only person I know that has taken apart enough of these to provide a real answer is Chris at Skyllaney.
Miles.
Beamsplitter
Regarding the post-war Sonnars made in Oberkochen, the general understanding is that Zeiss began to use UV glue, as opposed to Canadian balsam, when the name-ring changed from Zeiss-Opton to Carl Zeiss (1954), but is it really that cut and dry?
I ask because...
I just acquired a Carl Zeiss 50mm f1.5 that has the faintest signs of separation in the rear, but it doesn't have the typical rainbow cast that seems synonymous of the UV glued lenses. This particular serial number is 'fairly early' into the Carl Zeiss name change era, which got me thinking of how exact the cut-off may or may not be.
I ask because...
I just acquired a Carl Zeiss 50mm f1.5 that has the faintest signs of separation in the rear, but it doesn't have the typical rainbow cast that seems synonymous of the UV glued lenses. This particular serial number is 'fairly early' into the Carl Zeiss name change era, which got me thinking of how exact the cut-off may or may not be.
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TenEleven
Well-known
Yes, the cutoff is not that clear it's more of a general guidance.
For example I have a 1,1 million Biogon that is still "Opton" so even Zeiss weren't that hard in their name-change and probably used up all the "Opton" engraved name-rings instead of scrapping them. I would say around 1.4 million (the next 1.5 Sonnar batch) is a more sure sign that your lens is going to be UV epoxied. That all being said, there are also many epoxy cemented lenses that are fine. They just are more likely to fail than the earlier variants where separation is somewhat rare.
Also, there are possibly other contributing factors. I discussed this with @Räuber a while back. Namely, Zeiss also cheapened the mounting of the lens elements; getting rid of the brass (later aluminium) tube the actual lens elements sat in, putting both the rear and front triplets into the barrel directly. This of course increases both mechanical and temperature stress for the elements.
For example I have a 1,1 million Biogon that is still "Opton" so even Zeiss weren't that hard in their name-change and probably used up all the "Opton" engraved name-rings instead of scrapping them. I would say around 1.4 million (the next 1.5 Sonnar batch) is a more sure sign that your lens is going to be UV epoxied. That all being said, there are also many epoxy cemented lenses that are fine. They just are more likely to fail than the earlier variants where separation is somewhat rare.
Also, there are possibly other contributing factors. I discussed this with @Räuber a while back. Namely, Zeiss also cheapened the mounting of the lens elements; getting rid of the brass (later aluminium) tube the actual lens elements sat in, putting both the rear and front triplets into the barrel directly. This of course increases both mechanical and temperature stress for the elements.