1949 ZK 5cm F1.5 Sonnar, on the M9

[Sonnar Brian]

Following the test of the experimental Leica Mount 1933 Carl Zeiss Jena 5cm F1.5 Sonnar, and the 1945 Leica Mount Wartime Carl Zeiss Jena 5cm F1.5 Sonnar "T" - a 1949 ZK Sonnar.

This lens had to be optimized for close-up, wide-open work on the Leica when received.

The fence: Wide-open at f1.5

100% crop.

This is a good lens.

At F4:

and Infinity at F1.5:

100% crop of the intended point of focus:

Looking around the frame at 1:1, the actual focus.

It's short of the intended focus.

Close-up and wide-open, the focus agrees with the rangefinder of the camera. At infinity, it falls short.

The only way that can happen is if the actual focal length of the lens is longer than what the RF of the camera is calibrated for.

 

[Sonnar Brian]

At F4, the sonnar infinity shift works in your favor- just like on a Jupiter-3 or Jupiter-8 that has been optimized for close-up and wide-open.

At F4, focus is closer -but not quite- to infinity.

100% crop.

close-up, and wide-open.

and F4:

and F1.5 again,

at f4:

Who wants to use a Sonnar wide-open, and at infinity anyway...

 

[Sonnar Brian]

This ZK Sonnar has a focal length "on the long side" compared with a Leica. Without a data Sheet for the lens, it is impossible to say how much of it was intended, or just learning curve. Sonnars are built to the Zeiss standard of 52.4mm, but you can move the optics around slightly to reduce the actual focal length. Tests of the Wartime LTM Sonnars showed that it matched the calibration of the RF of the M9 across the entire focus range.

The Jupiter-3 is definitely built to the Zeiss standard. The Data Sheet that came with mine proves that it is by design.

 

[gzuiko]

Looking at the first few shots, I thought I saw some of the same "glow" that the Tokyo 5cm f1.4 exhibits. But maybe that's not what it is. The bokeh is generally very good. The foreground OOF in shots 5 and 7 is not as pleasing to the eye.

Do you find this lens drastically different than the other J-3 or Sonnar lenses you've tested?

I've got the Sonnar bug I'm afraid. I have a 1959 J-3 on the way from Grizzly33bear. I hope it's as good as some of the ones I've seen you test.

Jim

 

[Sonnar Brian]

Side-by-side with a Sonnar "T", hard to tell the difference. Side-by-side with a KMZ J-3, also hard to tell the difference. A good ZOMZ J-3, once they hit their stride ~1958, also hard pressed to tell the difference. Compared with a newer J-3, the later lenses pale by comparison.

 

[dexdog]

Interesting test, Brian- thanks for posting all the photos. I find the variations in the various WW2 Sonnars, ZKs and J-3 to be intriguing. The latest ZK seems to be a good one as you noted, exhibiting very good resolution on the fence post shots. I also concur with your assessment that it is hard to tell the difference between the various lenses, once properly calibrated to leica standard. I have tested the early 1960s ZOMZ J-3 that you tweaked and found it to be as good (or better) than some of my other Sonnars and clones.

 

[gzuiko]

Must admit I don't know who made the J-3 that's on it's way from Ukraine. All I know is that it's from 1959 serial number wise. I bought it after losing out on an auction for the uncoated black and nickel Sonnar, then a day later I got a "second chance offer" on it. Had to jump on it. And even though there is what appears to be internal separation, the outside of the glass is flawless. Take great pictures and I love it. Much nicer contrast than my black and nickel Tessar.

I'm really enjoying reading about your experimentation with Sonnars, Brian. Thanks for all the good info.

Jim