Transition CZJ 5cm F1.5 Sonnar compared with an Early 5cm F1.4 Nikkor-SC.

[Sonnar Brian]

From the article I wrote when comparing my Nikkor 5cm F1.5 with the wartime CZJ 5cm F1.5, "Bogdanovitch wrote of the Nikkor lenses “The lenses are of excellent color correction and perform better at full apertures than do Zeiss lenses.” Dr. Karl Bauer, President of Carl Zeiss, Inc. USA, was furious with the Times and threatened to drop all advertising with the paper. The Times allowed Zeiss to run a statement that the “Zeiss lenses being tested were not true Zeiss lenses.”

I wanted to compare a Transition lens with the Nikkor. I received a very nice Transition CZJ 5cm F1.5, very clean glass- in Contax mount. I also picked up a J-3 in LTM that needed a thorough cleaning and some polishing.

I used the retaining ring from a ZOMZ J-3, as this lens had none. I polished the retaining ring down about 0.05mm, then used a 0.01mm shim. F1.5 came up to the index, and focus is good through the range. Transition lens made in the 1940s, J-3 made in 1973. Somebody had a standard for starting positions for threads. This is one of the nicest that I've handled, glass is very clean.


Wide-Open on the M8, focus is perfect close-up and good enough through infinity.


Looking at the last image- this lens has a centering problem. The field curvature is asymmetric.

 

[Sonnar Brian]

I used the Nikon Z5 for the comparison test. I used a inexpensive LTM to Z-Mount adapter, which is spot-on with infinity for both lenses.

First up, the Transition Sonnar.

F1.5 and F4 Pairs.

 

[Sonnar Brian]

Transition Sonnar, wide-open and close-focus.

 

[Sonnar Brian]

The Nikkor-SC 5cm F1.4, 326xxx- Early Made in Japan. This is before the diameter of the optics were enlarged sometime around 344xxx.

 

[Sonnar Brian]

Wide-Open, 3ft to match the Transition Sonnar.


The edge-to-edge sharpness of the Nikkor is much better than the Transition Sonnar. I noted high field-curvature for the Sonnar when using it. Center sharpness is good. The Transition Sonnar appears to be decentered. I have seen these lenses "hot-Mounted" into the fixture for aligning the triplets. This means mounting the glass before the balsam is dry, and hope the fixture is accurate enough to provide alignment.

The Transition Sonnar has the same rear triplet as the post-war CZJ 5cm F1.5. That will be the next lens I compare this with- a "true Carl Zeiss Jena Sonnar.

 

[Sonnar Brian]

Since I'm using the Z5, let's use the minimum focus of the Nikkor.
Wide-Open.

I have an early 1952 J-8 with German cut/coated glass that I pulled the focus stop screw. I can focus this close with it. Will use it on the Z5 soon.

 

[Sonnar Brian]

After 20 years of cherry-picking Sonnars and Jupiters, I have some of the best ever made. And for many of them- I made them better by taking them apart and fixing some problem on them.

This transition Sonnar is one of the worst that I've ever seen, including 9 of 10 Valdai Jupiter-3s. I converted it to Leica mount, but did not disassemble the lens. After seeing the results, went ahead and took out the front element and middle triplet.
1) The middle triplet is loose in the barrel, the diameter of the fixture is slightly too big. Usually the middle triplet is a tight fit. The retaining ring would normally help center the group...
2) there was a burr on the side of the barrel that pushed the triplet off center.

SO- remove and clean the glass, get rid of the burr, put the glass back and "tap ever so slightly" on the side of the lens as I use the spanner to tighten it down. The theory being vibrations while tightening will help place the lens.

 

[Sonnar Brian]

Quick test on the Z5. The field curvature is a bit more symmetric, ie does not run from the lower right size to upper left, close to infinity.


Last shot at F1.5 only.

 

[Sonnar Brian]

Not the Sharpest Sonnar I have, not by a long shot. But figure this Transition Sonnar was being built in Leica Mount after the war. Many made there way back to the US and elsewhere. Anyone comparing this lens against a Nikkor-SC 5cm F1.5 or 5cm F1.4 would certainly note the Nikkor is much better. So back to " Dr. Karl Bauer, President of Carl Zeiss, Inc. USA, was furious with the Times and threatened to drop all advertising with the paper. The Times allowed Zeiss to run a statement that the “Zeiss lenses being tested were not true Zeiss lenses.”"

The purpose of this test was to compare the available Zeiss lenses of the day against a Nikkor. Fair to say- it is not a real (regular production) Zeiss lens...

 

[Sonnar Brian]

The transition Sonnar is bad, really bad.
I have several v4 Carl Zeiss Jena 5cm F1.5 Sonnar "T" lenses, including one that had (past-tense as of this afternoon) a front element with more cleaning marks than I like. The Transition Sonnar has a near perfect front element. I suspect it's the Triplets that are the problem. SO- the question, are the front elements between the two lenses interchangeable? That would go towards answering the question if the Transition Lens has Zeiss glass. I popped the name-rings and the front elements: same diameter, fit perfectly. I swapped the two.

First up- how did the 267xxxx v4 Sonnar do with the new front element? It's keeping the new one, will not give it back.
I even did the super-boring brick-wall test.
At F1.5, click for full-resolution images.


At F4,

 

[Sonnar Brian]

Fence Slats, F1.5



F4,


Distance, focus on tree in the middle of the yard, F1.5.

 

[Sonnar Brian]

Transition Lens, F1.5-


At least the front element did not make it worse.

Slats, F1.5



Back-Yard, F1.5

 

[Sonnar Brian]

For comparison- the v3 5cm F1.5 Sonnar, "Made in Germany" with coated front element and rear triplet.

F1.5,


F4,


Slats, F1.5

 

[Sonnar Brian]

V3 again,

F1.5, Back Yard



So what's it all mean... The front element of the Transition Sonnar is really good, and interchangeable with other v4 5cm F1.5 Sonnars.
Next up- I'll probably swap out the middle triplet of the transition lens. My money is on it as being the problem.

 

[Sonnar Brian]

I had some time to look at the middle triplet of the transition lens. First I tried swapping the middle triplet from a 1951 J-3. It fir into place, but threw the focus off dramatically- shifted the focal length to the longer side. Severe back-focus, object at 30m was in focus with the lens at 4m.


All at F1.5 on the M240, focus via the EVF.
The image itself is greatly improved, but focal length is too long to agree with a Leica rangefinder across range.

The diameter of this Middle Triplet is 0.15mm larger than the original. It fit nicely into the barrel, not too snugly. The Centering problem is gone.

SO: The problem is the diameter of the original triplet is too small for the barrel.
Whoops.

 

[Sonnar Brian]

This is with the original Triplet back in place in the barrel.
I wrapped the glass with Copper Tape. The triplet now fits into the barrel without bouncing around.

Again on the M240. Single shots at F1.5.

 

[Sonnar Brian]

Pairs at F1.5 and F4,







Much better than it was. This lens is almost 80 years old now. These might be the first decent images ever taken with it.

 

[dexdog]

Nice work, Brian!

 

[Miles.]

This 666 lens has provided quite the saga. Good work, Brian!

 

[brusby]

I used the Nikon Z5 for the comparison test. I used a inexpensive LTM to Z-Mount adapter, which is spot-on with infinity for both lenses.

First up, the Transition Sonnar.

F1.5 and F4 Pairs.
View attachment 4861531

Funny, I thought this image was the most artistically and aesthetically pleasing of the entire group, even though you determined the optics were not right. To my eyes, there's something kinda soft, dreamy and just pleasing to look at about the way it handles things. I'd be very happy to use this lens just as it was configured here to do some dreamy portraits. Not saying I don't like the corrected optics, just that this one immediately caught my attention. Thanks for the analyses.