Leica Showcase KMZ 3.5cm F2.8 Jupiter-12 in LTM

The Jupiter-12 is a copy of the wartime Carl Zeiss Jena Biogon. Early one, before 1956 or so- have German Glass. This 1952 has a Serial number stamped into the rear module that identifies it as a 1943 Zeiss Biogon.

When received, the focus was off on the Leica. This is common with Russian lenses, which are made to the Zeiss standard. The shim typically has to be thickened, and this one required an extra 0.1mm. My opinion- KMZ tends to be the best of the Russian manufacturers. ZOMZ- close second. This lens, with shipping- was under $100. Puts it as the best of the bottom for Leica mount wide-angle lenses.

The J-12 has a massive rear element, and will NOT fit on a Canon P or Canon 7. It fits well on the Leica M3, M8, and M9. I would NOT use it on the CL or M5.

At F2.8, then F4.
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defektive

Veteran
Location
Tasmania, Australia
Real Name
Sam
Brian, I have one of these that has been sitting on the shelf for twelve months waiting for me to match it to my M6. Can you point me in the direction of where to find instructions of the shimming process please?
 
I photographed this lens as I disassembled it. I will put them together in a PDF and post. I did the same with the J-3, in great detail.

The short of it: unscrew the back element; then unscrew the front module from the focus mount; reveals the shim. It is the same as used in the Jupiter-8. Unscrew the entire front section using a rubber cork or mouse pad on the serrated front. The front optical group comes out of this section using a spanner. The last step- only if you need to flood clean the aperture blades.
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Penfan2010

All-Pro
Location
NJ, USA
Real Name
Ed
Evening Walk with the 3.5

A few photos I took on an evening walk around our neighborhood park with the KMZ 3.5 on my M8; PP on LR 4.4. Was going to do BW conversions, but I do like the color of this old Russian lens.

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Penfan2010

All-Pro
Location
NJ, USA
Real Name
Ed
One more at the end of the evening walk; for the last 8 years or so, I have not had any luck getting a photo of my younger son with a decent look on his face.

The KMZ is nice and sharp and contrasty. BTW, I don't have an IR cut filter for the KMZ, so his dark blue hoodie is exhibiting the trademark M8 color shift.

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CaptZoom

Veteran
Nice photos Pen.
I don't know about the thickness of the M9 sensor versus the one in M8. This lens was amongst my favorites on the Leica clone I used to have. The minuscule size and good IQ make it really attractive.
 
Man...I've been too chickensh*t scared to put this on my M9! But apparently it mounts without damaging the camera, huh?

I have used it on the M9 without problems. Mine is from 1952- and the rear module is shown. Later J-12's got rid of the protective metal ring around the rear element.

The only problem I've had is using on a Canon 7 and Canon P. I also think the Canon VI would be a problem.
 

CaptZoom

Veteran
I have used it on the M9 without problems. Mine is from 1952- and the rear module is shown. Later J-12's got rid of the protective metal ring around the rear element.

The only problem I've had is using on a Canon 7 and Canon P. I also think the Canon VI would be a problem.

Thanks Brain for taking the risk! I get my M9 back some time next week. I'll try the Jupiter and report back. I'll do some research to figure out when my Jupiter was produced.
 

Mr_Flibble

Top Veteran
Location
The Lowlands
Real Name
Rick
I recently CLA'd an early (1952) Jupiter-12 for a friend. He had picked it up in Budapest a few years back.
Problem was the whole lens module was positioned too far forward due to a shim not seating properly and jamming in the screw threads.
I also took the opportunity to give the focus helical a fresh lube job.

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After properly seating the shim the lens appeared to be calibrated correctly for Leica.
Some unprocessed Leica M-E test shots.

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So, decided to buy one for myself. Gone with a late black version. Hopefully it won't be too much of a lemon ;)
 
1952 is a great year for the J-12.

The early ones are the best, KMZ made J-12's are better than the others. Later ones can be really good, once adjusted

The above 1977 lens was really good. I had a 1960 J-12 that was so bad that I made it into a 35/2 with a Wollensak Raptar.
 

Mr_Flibble

Top Veteran
Location
The Lowlands
Real Name
Rick
The black J-12 arrived today. It's manufactured by the LZOS plant. Going by the first two digits of the serial number this one is from 1974...if that way of dating them holds true

J12Test00.jpg


Aperture blades looked like they were freshly oiled :whistling:. And there was some paint wear on the rear lens edges and bezel.
Apart from that it seems to focus well using the rangefinder on my M-E (and a Leica LTM-to-M ring)
But the focus scale is off a bit once focused using the RF.

Some unprocessed test images;
J12test01.jpg

Focused on the eye - wide open - Behold my glorious Corona lock-down induced beard!

J12test02.jpg

Focused on the flower in the center - f/4

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Focused with the RF at one meter on the label - Wide open
Scale indicates roughly 1.1m
 
Location
Sydney, NSW, Australia
Real Name
Alan
A few shots from my black 1980 J-12 LZOS factory. I purchased it from what seems a reputible Ukraine ebay seller, Retro Photo. It had been CLA’d, Leica tuned
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etc prior to sale. Seems to be accurate on my M10 but if in doubt I resort to the Visofles EVF. Photos taken in May whilst in lockdown. I live on the edge of a national park about 20km from Sydney’s CBD so with many walking tracks it opens opportunities as the seasons come and go.

P.S. Forgot to mention, I also have an older, silver, KMZ from 1959.
 
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