Jupiter-8m (Brian Sweeney modified) – Finding My Perfect Classic Sonnar PT8

If you’ve been following this series of posts about the path I’ve been walking to find myself a perfect classic Sonnar, you will have likely come to the conclusion that I’ve become a big fan of the Jupiter-8. My experiences finding such an appreciation have culminated in a fairly unusual and – at least without significant knowhow – difficult to repeat outcome. But considering how happy I am, it would be entirely remiss not to document it.

There are many types of Jupiter-8 lenses. They were made for two different mounts, and over the years went through a fair amount of changes to their physical appearance. But as I have talked about throughout my the last few post on the subject, there has never been a Jupiter-8 built to perfectly focus on Leica rangefinders. They were all designed for use on either Keiv cameras that has a Contax mount (the Jupiter-8M) or for Zorki cameras that had a 39mm thread mount that was very similar to Leica’s thread mount, but had a slightly different register.

As such, if you want to mount a Jupiter-8 on a Leica camera you have a few options, none of which are entirely perfect. Firstly you can just deal with the incorrect focusing as I talk about here – this is obviously less than ideal, but workable nonetheless. Another option is to adapt a Contax mount Jupiter-8M lens as I do here. This works, but Contax to Leica mount adapters are expensive – even the cheap ones. Finally you can modify one. I had a go myself as I talk about here, but as you can see, unless you’re fairly well skilled, there are still pitfalls to that process too. The final option – which is what resulted in the lens I have here – is to find someone with the skills to modify a lens for you. In my case, I spoke to Brain Sweeney.

As I mention in my Jupiter-3 post, I actually got in touch with Brian to chat about the idea of fixing up a J-3. But after chatting for a short time via email, most notably with me discussing how much enjoyment I’d had out of my Jupiter-8M he convinced me of a path that he felt might lead to a very positive outcome for me. He suggested that rather than spend a lot of money on a less ropey Contax mount adapter, that instead he could potentially remount my Jupiter-8M into a Leica thread mount lens. In fact, before that, he first suggested I buy a Jupiter-8M already remounted from a seller on eBay in Russia. There is, as he pointed out, someone in Russia who – for reasons perhaps only known to themselves – is taking Jupiter-8M lenses apart and forcing their optics into the shell of an industar-26; a Russian 50mm (ish) f/2.8 lens.

Having not tried one, Brian guessed that there might be a chance that this Russian knew what he was doing and I would find myself with a Jupiter-8M remounted and collimated for a Leica camera. His idea being that if the lens came from Russia working, then it was problem solved, if it didn’t he would happily take my – already proven to be really nice – 8M, scrap the glass out of the Russian hack, and insert mine.

As it transpired, the lens I bought from Russia was – optically at least – completely shot. It didn’t focus as it should, it was scratched and filled with dust. Secretly, I was quite happy about this, as it meant that I got to have Brain perform a touch of his magic on a lens for me. So, off it went on its second long haul trip over to the states. With it I also sent my J-8M and my Contax Zeiss Opton for a once over – I will come back again to the latter another day.

After a few days, Brian got back in touch with a very agreeable bill for the work and some good news. Rather than remount my Jupiter-8M he had decided that a lens he already had contained even better optics. After what sounded like a bit of a nightmare he had managed to unpick the mess the Russian ebay seller had made and had perfectly mounted his set of optics into the Industar-26 shell. Fortunately, the industar already had a pretty smooth focusing helicoid and aperture, so there was no issue there. Another few days passed and I had in my possession what effectively amounts to a perfect (for me) Jupiter-8.

Unfortunately for the sake of my new ltm Jupiter-8m I found myself a little sidetracked. I’d picked up a Jupiter-3 by this time and had on loan from Lomography their Russar 20mm so was concentrating on shooting those. Something else interesting happened though, and that was my purchasing of a Leica Monochrom. I actually can’t begin to tell you how much a big deal owning one of these cameras is for me. I’ve wanted one for years and now owning one and being able to shoot black and white digital in as pure a way as is imaginable – it’s just brilliant.

What was interesting and relevant to this story about the Monochrom is that I found myself with a camera that works very differently to any I’ve shot before. I shan’t go into it now, but in brief the Monochrom clips highlights with some enthusiasm if you aren’t careful with it. Put modern glass on it, and you can quickly find highlights blocking out. Just as an experiment, I mounted the ltm Jupiter-8m – I wanted to see if the older lower overall contrast glass would take an edge off the overall contrast in the result. What actually happened felt like a revelation.

It felt like shooting the Monochrom gave me a much clearer window to a lenses character. I talked about this in my early impressions post about the Monochrom, but it was this lens that made me realise it. The wonderful thing in seeing this lens’s character so clearly was seeing how much I loved it! Until the 7Artisans 50mm f/1.1 turned up, I was shooting it exclusively, and finding myself repeatedly with that wonderful feeling you get when it just feels like all the pieces of the puzzle come together to create an image that really works.

This is probably my favourite lens in this process so far. This habit it seems to have of causing such a strong flare when it’s shot wide, and the fact that it just seems to ooze the 3D look which I love so much in Sonnar lenses are just the traits that I’m looking for. Of course I might be applying a bit of extra affection to it for the fact that it feels like a unique lens that I had to jump through a few hoops to own. But that’s fine by me, as one way or another, I’m extremely pleased with it! Thanks Brian!

Some photos

Hannah & Murph

Connie Laughing

Family snap

Family snap




Finally, being completely honest, discovering the Jupiter-8 to the extent I have and latterly having this lens put together has definitely now changed the course of this Sonnar project. I can say for certain that this process is no longer a search for a lens. This lens, and in fact the Jupiter-8 that I modded, could easily put an end to this by themselves. They really are wonderful lenses that have just the sort of balance I’m looking for. In short – and as I alluded to at the beginning of my previous post – I don’t feel that I’m this searching for a perfect classic Sonnar lens; I feel like I’ve found that already. From here on out, I feel like I’m now just feeding a Sonnar obsession… Regardless, I shall continue to document the lenses I discover.

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23 thoughts on “Jupiter-8m (Brian Sweeney modified) – Finding My Perfect Classic Sonnar PT8”

  1. Hamish,
    You realize that you put all the rest of us in a very difficult position, unless Brian decides he wants to make a career of modifying Jupiter 8s for the rest of the world.

    Here in the USA, we have a seller named “fedka”, who has cameras selected from Russia, and they are often serviced in Russia before being accepted by him. Out of curiosity about Contax, I ordered a Kiev IIa (ca. 1956) with a Jupiter 3 lens. The Jupiter 3 lens was actually quite astonishing in its quality. It easily competes with my Nikon 50mm f/1.4 SC lens in Leica thread mount.

    Well, along this time someone offered a parts Jupiter 4m for only the price of postage. It turned out to be the complete camera, just totally taken apart. It did contain an fairly modern Jupiter 8M which had a filter ring dent on it, meaning it had been dropped at some time. Comparing the two on film, it was clear that the Jupiter 3 was far ahead of the 8M. I wondered if the 8M was even a bit off focus sometimes. Anyway, it’s not a fair comparison as the Jupiter 3 is pristine, and looks new even (but it was born in 1964). Clearly the Jupiter 3 has been babied all its life.
    I sent the parts 4m and jupiter lens off to Fedka as a gift.

    I guess the point of my note is that condition is everything with these vintage lenses. That, and you need to test them yourself.

    1. I completely agree – throughout my experiments with these old sonnar lenses, I have tried to keep that in mind as much as possible. The great thing about playing with old lenses is that damage and imperfections don’t always detract. Character traits brought on by a bit of haze or some scratches to the coatings might even add to the look any particular individual might be after – this just makes the whole process so much more interesting I think

    2. I just received a Jupiter-8M mounted in a Canon 50/1.8 focus mount, a quick test using my TTL viewer and my M8- it is spot-on.


      I contacted the Ebay sller to let them know how happy I was, and asked who did the lens. The seller custom mounted the J-8M in the Canon mount, and let me know they would be doing more.

      I could not buy the Parts to do this for what I paid for the lens.

      1. Brian,

        Any chance of finding another perfect Jupiter 8 with 0.7 meter focus? I gave mine to a friend (who also followed me in buying the Jupiter 3+).


        PS: The 1937 f/1.5 and 1943 f/2 are both still doing great. The f/1.5 usually for color and the f/2 for black and white.

  2. Hamish – the rendering on those first 4 photos is wonderful. I now understand what you were talking about in the pub! We’re they shot wide open on the M9M? This has definitely got me curious. I’ve just spotted a guy on evil bay selling what he claims are NEW (i.e unused) Jupiter-8s from 1973 for £75…. wondering whether to pick one up now! Might be a better idea than buying several cheaper used ones while trying to find a gem.

    1. Hi Julian – yes wide open; stop down slightly and the flare calms right down. The problem with buying any J-8 is fundamentally that they aren’t compatible with a Leica. Buying a new one doesn’t change this. This is fine as long as you are happy with the compromises, or can make the mods. That aside, it’s also worth thinking about what you lose by buying an older, possibly slightly flawed lens… pick one up for £20 (or whatever) that’s not perfect and contrast might be lower (or whatever) but the frustration that comes with the nonsense of incompatibility is easier to swallow…

      1. Yes, that’s probably good advice! Just had a Konica M-Haxanon 50 f/2 arrive in the post, so will see how I get on with that for now… they tell me it’s a good substitute for a 50mm Summicron v3 but was only 1/3rd the price. Build and feel are first rate – will shoot some rolls on the weekend and see how it looks.

  3. Tantalising article Hamish! I’d noticed that highlights can tend to get clipped severely on the Monochrom. One of the few negatives I’ve encountered on a camera that has been a revelation to my photography. I just thought it was something i had to live with until i read this article. If the converted Jupiter 8M was actually available i would buy one. Aargh!

    1. There are plenty of other “vintage” lenses that work very well. The thing to remember though is that lens contrast and overall contrast are separate – You can’t avoid clipped highlights, just potentially make the transition to clipped highlights less obvious/strong

  4. I admire your passion for the Sonnar. You’ve gone to extreme lengths so far to find the perfect lens to fit the Leica.
    It makes for a fascinating read.
    However, while I understand your love of Leica camera bodies, would it not be a better route to find the perfect lens then find the correct camera body to accompany it?

    1. I know what you’re saying Jeremy, but the perfect lens wouldn’t be the perfect lens for me if it didn’t fit a Leica…

  5. We got lucky on this one! I had two J-8m’s in Contax/Kiev mount, this one focused perfectly in the hacked I-26m mount. The Russian lenses had about a 1% tolerance on focal length, the one you have is likely on the short end, which means better agreement for Leica. I’ve had several J-8m’s, this one is by far the best. I’m happy it has a good home.

    As far as images from the M Monochrom being flat… Nothing that a good FORTRAN programmer cannot fix-up.


    1. I’m happy it has a good home too! Thanks again Brian! Have you a link to more details about what you do with your Monochrom files?

  6. I “dusted off” an old FORTRAN program that I wrote in the early 1980s for use with custom digital sensors and modified it to read DNG files, apply the Gamma curve to the 14-bit data, and store it as 16-Bit DNG…
    Photoshop, Silver Efex2, and Lightroom can handle the 16-bit pixels in the files. Why 16-bits? That way after applying the curves, each new pixel value is unique- don’t get lumped together in the same intensity bins. That was the 1980s for me. The program “batch processes” all of the files. It runs under “DOS” and is written for “Phar Lap extended DOS”. I use that for embedded systems. Be happy to give away the source code for anyone that wants it.

    1. Brian, thankyou for sharing your knowledge. Your comments always catch my attention and I never cease to be amazed at the extent of your knowledge and willingness to share it.

  7. Pingback: The Canon 50mm f/1.5 LTM Review - Exploring the Classic Sonnars Pt.9 - 35mmc

  8. Pingback: Bringing a New M-Mount Sonnar Lens to Market - An Interview with Chris Andreyo, Skyllaney Opto-Mechanics - 35mmc

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