Range finder coupling on Jupiter 8

Discussion in 'Leica and Rangefinders' started by johncox, Sep 27, 2012.

  1. I am looking at getting a Jupiter 8 possibly and was wondering how the range finder coupling stacks up on the Jupiter lenses that are out there. Is it worth my time and money to get one? Or is it more feasible to just buy a west German Summicron.
    Thanks is advance.
    John
     
  2. The rangefinder coupling on soviet LTM lenses works the same as on other LTM lenses. On 50mm lenses, there is a ring protruding from the back and moving together with the optical block. On most tele lenses there is a tab only. The latter might cause problems when mounting them on real Leicas. You should set the lenses to the close-up distance prior to mounting them, this way the tab does not protrude too much and will pass the roller cam easily.
     
  3. The Soviet lenses may or may not be calibrated to a Leica body, depending on your luck. The lens may need to be dissassembled and shimmed to be accurate. A Canon or Leica lens would be accurate without luck or shimming, but they cost more. On a budget I recommend Canon lenses, as they are high quality, focus properly, and less expensve than Leica lenses.
     
  4. The Jupiter-8 5cm F2 is the lowest risk Russian lens. They may or may not focus spot on with a Leica camera. Typically they do. Those who have had bad luck jump on the "it was built to a different standard soapbox". These folks often have simple minds and they cannot except that the issue is really complex and murky at best. Their brains want a black and white answer to a complex murky subject, thus these folks probably should buy a 1000 buck new summicron! :)
    The focus ring on a Jupiter-8 is aluminum and wears. Thus if it tracked well in 1956 it might be worn and not track as well today. The follower on a Russian camera is not a roller bearing like Leica, it rubs and is a cam finger.
    An analogy is Russian stuff is like Harbor Freight stuff. Now you are asking if 50 year old Harbor Freight stuff that has 4 prior users is going to be still great. You are asking if all Harbor Freight model 12345 works well 1/2 century later after 4 owners.
    12 years ago a Zorki plus Jupiter-8 and case cost me 5 to 7 bucks as a buyer who bought them in bulk to resale on Ebay. They were like old instamatics in the usa ie old stuff folks did not use.
    This question is like asking in the year 2062 about automotive sockets on a forum. You want an exact answer if a Harbor Freight socket built in 2012 in China is as good as a used Snap On Tool socket
    (1) The two sockets could have built to the same exact dimensions but the HF one got worn more. The snap on one could have been used on an impact wrench and ruined. Or both could be never used much and both good 50 years later.
    (2) The two sockets could have been built differently and the HF one always more sloppy.
    (3) A mix of 1 and 2 thus a blurr in what one gets 50 years later
    Because used Harbor Freight and used Russian lenses has a risk you are wise to not spend too much money in case you get a dud.

    Even non Russian LTM lenses have some issues too. I have owned Canon 50mm F1.2 LTM that focused well and others that had a bias and did not focus/track well on a Leica LTM body.
    This subject is vexed at best. Many folks place all their opinions based on others goofy opinions or base it on tiny samples thus folks preaching varies wildly.
    Here I have used many Jupiter-8's that track perfectly on Leica LTM bodies. This bothers some folks
     
  5. The Jupiter-8 and Jupiter-3 are built to the Zeiss standard focal length of 52.4mm. This is the focal length given in the data sheets of several new-old-stock Jupiter-3's that I bought. The Leica is calibrated to a nominal 51.6mm focal length. Typically increasing the thickness of the shim by 0.1mm optimizes a J-3 and J-8 for close-up and wide-open on a Leica. Stopping down to F2.8 is best for infinity after making this adjustment. There is enough deviation in focal length, and the shims of the lens that each should be tested individually. The formula for computing the shim is given here:
    J-3/ J-8
    Infinity

    1/(focal length)= 1/(distance)+ 1/(backfocus)

    1/52.4mm= 1/infinity+ 1/(backfocus)

    1/52.4mm= 1/ (backfocus)

    back-focus= 52.4mm



    at 0.9m

    1/52.4mm= 1/(900mm)+ 1/(backfocus)

    0.01908mm= 0.001111mm+ 1/(backfocus)

    0.07969mm= 1/(backfocus)

    Backfocus= 55.6514mm



    Travel from Infinity to 0.9m: 55.2976-52.4 and is 3.2514mm


    Leica:

    Infinity

    1/(focal length)= 1/(distance)+ 1/(backfocus)

    1/51.6mm= 1/infinity+ 1/(backfocus)

    1/51.6mm= 1/ (backfocus)

    back-focus= 51.6mm



    at 0.9m

    1/51.6mm= 1/(900mm)+ 1/(backfocus)

    0.019380mm= 0.001111mm+ 1/(backfocus)

    0.0182688mm= 1/(backfocus)

    Backfocus= 54.7380mm

    Travel from infinity to 0.9m: 54.7380- 51.6 and is 3.1380

    The difference in travel between 3.2514mm for the Jupiter-8 and J-3 and the 3.1380mm for the Leica can be made up by increasing te thickness of the shim, and relying on the Sonnar focus shift for infinity.
     
  6. http://fedka.com/catalog/product_info.php?cPath=24&products_id=74

    http://fedka.com/catalog/product_info.php?cPath=24&products_id=571

    Fedka lists the technical specs of the Jupite-8 and Jupiter-3. Not to hard to figure out they are made to the Zeiss standard. Once you understand the reason why a Jupiter-8 and Jupiter-3 does not focus properly on a Leica, it's easy to correct for the difference.
     
  7. Brian;
    The flaw in your presentations is many of us have many of our Jupiter-8's that do focus spot on at infinity and mid and close up.
    Thus these great J8's do not need ANY shims
    Thus these groups of J8's were built to the Leica standard
    That is why there is so varied opinions on Russian lenses.
    Your theory does not explain how many of us have owned many J8's that do focus spot on.
    The best Russian lenses I have are bought from not the USA.
    In the early days of Ebay I sold many many hundreds of Zorki's with J8's. The first J8 I used I bought back in the 1970's for 2 dollars as used.
    It was not until the internet came out that these theories started.
    They are basing these on lenses that are used, 1/2 century old, worn and with a rather poor build quality that varied.
     
  8. There is no flaw. There is no theory. There are Specification Sheets for the lens, and the laws of physic. The specificaltion sheets give the focal length as being the Zeiss standard. The formula for focal length gives the resulting error.

    I've shot with over 100 Jupiter-8's and Jupiter-3's. Most do better after being adjusted. The Depth of Field of the J-8 is enough to mask the difference on lenses that would benefit from shimming. The Jupiter-3, the depth of field is not enough to cover the difference. You can either adjust the shim, or change the focal length to match the Leica standard- then adjust the shim. On my 1950 KMZ Jupiter-3: I adjusted the focal length and then shimmed the lens. It's perfect on my Leica M9 across the entire focus range used wide-open. It was unusable before the adjustment.
     
  9. Of course, you can use a J-8 on a Zorki or Fed- these cameras are built to work properly with a lens made to the 52.4mm standard. The problem only comes in when you use the lens on a camera made to the Leica standard. These include the Leica, Canon, Nicca, Leotax, and Tanack cameras. I have those. I also have a two Zorki 3M's. I adjusted the rangefinder on those to work with the Leica Standard. I use a Nikkor 5cm f2 in Leica mount on one of them. I modified a Nikon S2 to focus perfectly with Zeiss lenses, over 10 years ago.

    To the OP: Buy the lens, try it out. If it needs to be adjusted there are a lot of instructions on the Internet for doing it yourself.

    Kim Coxon hosts repair instructions for the Jupiters and others here:

    http://pentax-manuals.com/repairs.htm
     
  10. For myself, I decided a long time ago to invest time into making Jupiter lenses focus correctly on a Leica. These are with a Jupiter-8 on the Leica M9, after adjusting the shim to correct back-focus. [​IMG] [​IMG] [​IMG] [​IMG] [​IMG] [​IMG] [​IMG] [​IMG] This is a 60 year old lens. cleaned, lubed, adjusted for the Leica.
     
  11. Brian;
    it is just your opinion that the all the J-8 Russian lenses are built to another standard.
    It is not a fact at all since others of us have used J8's that WORK WELL ON A LEICA AS IS with no hacking no shimming.
    at best I think you want to believe all Russian stuff was built to another standard based on assuming.
    Having used Russian LTM stuff for over 35 years I think is is so sad that you can be so narrow minded.
    i have used many J8s that DO track well on a Leica body. ie with no shimming ie THEY FOCUS GREAT AT ALL DISTANCES.
    It is dangerous to do the lay thing and base a global conclusion based on a small sample.
    That assuming is dangerous, you make a broad brush statement of an entire population based on your limited sample. Then you cull out data points that do not fit your theory to promote the lay theory as real.
    Since I have bought brand new and used Jupiter-8 from the original owners and a had many of them work OK on a Leica they do not have to modified at all. This bothers you since basically I am saying your theory is bogus or BS. ie some of us have used J-8's for many many decades and many of them do work well on a Leica. My take is these were built better. Your take is you ignore others saying they have used J8's that work well on a Leica.
    If the lens focuses spot on all all distances it does not have to be shimmed. IT WORKS OK FROM THE FACTORY!
    look at how we differ.
    (1) you state that all J8's require a mod to work well on a Leica
    (2) My experience is that more than 1/2 of the J8's I have used focus well with no hacking
    (3) You throw out others experiences of them working OK to promote your flawed theory.
    I suppose if you fool with 30 year old used Harbor Freight lathes and find chucks are a little off a Morris Taper #3 you will say they were ALL built to a different standard?
    How about the concept the design varied and the output varied?
    How about the concept that there were different builds and different designs and different design targets?
    How about the concept that ignoring cases that do work spot on is called cooking the books to fit an agenda?
    Having used many a J-8 that focuses well on Leica my stance is you have a very flawed lay biased theory based on few samples.
    My first J-8 and Zorki was bought brand new in the early 1970's. This J8 was lended to a friend who bought a Leica M5 to play with. It did not have a focus issue then either
    The J8 had many different builds and at different factories over about 3 decades. Many millions were built.
    Just because your tiny group of J8's did not focus well does NOT mean that ALL of the many many millions of J8's all have to be fixed to work on a Leica.
    Since some of us do not have to mess with our stock J8's to work on a Leica is no reason to cull out these to fit an agenda.
    It seems you have a hard time accepting that others have used un hacked J-8s and they focus just great on a Leica and any mod will ruin them?
    There is nothing wrong with fixing poor examples of a lens. If the lens works well on a Leica then there is no reason to mess with them.
     
  12. Dante Stella over a decade ago preached that all Russian stuff was built to a different standard, thus Brian you are not alone on this theory.
    What is odd is culling out the cases where J8's do focus well on a Leica as is with no mods. ie a factory new old stock lens or one bought new eons ago.
     
  13. Yuri- if you have the manufacturer's inspection sheets that came with new lenses that show they are "51.6mm", I would like to see copies of those posted. Following the serial number of any built to a Leica standard would be of interest. Every data sheet from a Jupiter-3 that I have seen shows it to be 52.4mm, 52.5mm, and 52.3mm. That is the Zeiss standard.

    10 years ago, most people advised staying away from Russian lenses. "Poor workmanship, poor quality control, poor materials" were often cited. I bought 5 Jupiter-3's and took them apart. Then I bought 4 new-old-stock lenses with the data sheets included. That solved the mystery as to why I was getting better focus by increasing the thickness of the shims on most lenses.

    As the manufacturer states that the focal length is 52.4mm, I believe it. Adjusting a 52.4mm lens to work optimally on a Leica is easy. My 1950 KMZ Jupiter-3 matches my 8 Leica mount Carl Zeiss Jena 5cm F1.5 lenses. 5 of the Zeiss lenses, I converted to Leica mount myself. As stated: once you know the difference, adjusting is easy.
     
  14. Oleg of "okvintagecamera.com" posted some tips on adjusting Jupiter-3's, and advised to get lenses built before 1964 with the removable rear optics fixture. These allowed the focal length to be reduced, by moving the rear optics in closer to the front. Real camera repair technicians have known how to adjust these lenses for a long time.

    The information about the actual focal length of the lenses came with the lenses when they were bought new. I've seen a data sheet for a later 1960s J-3 that listed the focal length as 52.4 +/- 1%mm. That would mean the later lenses could run a range from 51.9mm to 52.9mm. Those on the short end would do fine on a Leica, those on the long end would need the focal length reduced to use on a Leica. I've seen both ends of the extreme.
     
  15. [​IMG] [​IMG] 1950 KMZ Jupiter-3, 5cm F1.5- wide-open on the M9. [​IMG]
    Focal length modified, optics cell remounted into a 1956 KMZ focus mount modified for 0.8m close-focus. I have several Summicrons. This lens gets more use on my M9. I would not trade it for a new Summicron (non-APO version). You can always buy a new lens. Getting a 62 year old lens that is THIS good- with perfect glass, not as easy. Spent a week getting the focal length and shim adjusted for full-range focus on the M9. The Russian lenses are well worth the cost, but be aware that they will most likely need a clean-lube-adjust. This is not hard.
     

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