Some interesting information On Jupiter-9 focus problem.

Graybeard

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I've been thinking about buying a fast 90mm-ish lens and have been considering the LTM version of the Jupiter-9 85mm/f2. These have a horrid reputation for focus problems.

I've had good luck dealing with the eBay vendor "grizzly33bear" and sent off a message asking if focus had been check on the lens she ("grizzly" is a lady, I understand) is offering. Here is my reply:

"The reason is very simple - J-9 lens (L39 version only) doesn't have exact registering distance setted - it must be calibrated together with camera! Not all sellers know about this fact unfortunately...

Originally, these Jupiters were delivered with set of adjustment rings (very thin paper rings) which should be used for exact calibration on the camera. Or, photographers could visit service shops, which also had these rings for calibration.

My lenses are adjusted to use with let's say 'average' camera - so the only 1 from 12..15 buyers reported problems with calibration.

So, I can't promise that all cameras will be working fine with lens, possibility that lens should be calibrated still exist... "

Surprising news to me and it would seem to explain the need some users have found for shims. I was planning to use the lens in a LTM/bayonet adaptor so once I get the shims right I'll never need change them.

FWIW and good light all-

Graybeard
 
the J-9 is not too hard to shim if you got a camera that is not a bottomloader.
my new J-9, which I bought in 1991, was hopelessly out straight from the factory.
I got sick of using it as a paper weight so with a bit of patience, I shimmed myself.
 
Its not just the shims (those paper or metal spacers which grizzly bear mentioned) that cause the focus problems. The shims would reposition the optical block in the correct place relative to the camera's focal plane when the lens is mounted. If that's the reason why the lens does not focus, then shims would be the answer.

BUT in many other J-9, the focus error is often with the focusing helicals. There are three meshed in the lens barrel- one moves the optics forward or backward to focus, another to move the lens RF cam back and forth to couple with the camera RF sensor, and a third in between to link the two.

Shimming would set the lens's correct focus for infinity and just about any distance within its focusing range. The focus would be right on film too, if focusing was done TTL like an slr. But in many cases (I had 14 J-9 at one time), setting the optic block right for correct infinity focus would not guarantee correct focus at any other distance setting when the camera RF is used for focusing.

The focusing helical is very difficult to put back correctly. Its three tubes can be put together many ways and only 1 would be correct. It's like working with a Rubik's cube.
An improperly assembled helical barrel would show proper focus at infinity (through the RF), but at the intermediate settings, they would be in error. For instance, an object 4 metres from the camera would be measured by the RF as 5 or 3 metres because of incorrect camming. Yet this same barrel could show correct RF focus at infinity.
 
This is interesting to read.
I am planning on stripping and relubing a J9 over the Christmas period, so I may have a look at the focusing in more detail while I am at it.
 
Well I managed to shim a J 9 so that it#s very sharp wide open at minimum distance.......yet everything after 1.5 metres is Out of focus . So basically I transformd it into a Macro lens.
Is there a way to shim them so that they work "normally"?
 
Well I managed to shim a J 9 so that it#s very sharp wide open at minimum distance.......yet everything after 1.5 metres is Out of focus . So basically I transformd it into a Macro lens.
Is there a way to shim them so that they work "normally"?

You can shim the lens to absolute perfection, but it will not focus right at certain distances if the helicoids aren't put back right properly. How the helicoids work will determine two important aspects in focusing RF lenses- first how the optical component is held relative to the film plane for proper focusing, and second how the lens cam moves to translate this movement into RF coupling.

If these issues aren't resolved, the lens won't be able to focus right- it will cause erratic RF measurement and improper placement of the lens from the focal plane.

Shimming is DONE so that the optical component is able to focus at infinity on the film when the lens barrel IS at its infinity focus setting. When the lens will focus only at close distances means that the shimming was too much.

One way to check the barrel helical for accuracy is to focus with it using the camera rangefinder. Focus at 1.5, 2m, 3m, and so forth up to infinity. If the RF images don't line up at infinity, the helical is already suspect. HOWEVER, some J-9 barrels would focus right at infinity, but will not at the intermediate distances. Measure actual focal plane to target distances- the distance scale reading on the barrel should coincide when the RF images line up. If a 2.5m object reads as 2 or 3 metres on the lens barrel, then the focusing helicoid as well as the lens' RF camming are really shot.
 
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Zorkikat,
I am really glad to see you active and discussing Russian lenses! I did not know you have 4 cats!

Well said about Jupiter-9. Putting it together if it was not marked during disassembly is almost impossible. My repairman charged double for Jupiter-9 repair, mostly because the lenses that come for CLA were worked on before and were not assembled correctly. So he would have to do this Rubik's cube from scratch.
So, to put it short - shimming the lens to work at infinity is easy, making sure it is assembled correctly internally is hard.
 
Just to make things clear, Yuri. What I meant was that you are a perhaps overly honest and concerned seller who won't sell something which may not satisfy a particular buyer. I really did want that J-9, having failed to get a Nikkor of the same specifications. In the end I got an Apo Lanthar from a friend who was visiting India. Slower, yes, but also small and handy -- and deadly sharp. I dare say the smaller maximum aperture may help a little.
 
the helical on my J 9 was spot on, the metre markings on the barrel coincided with the rf and the actual distance from the film plane so the focus helical was not taken apart.
this lens was still factory new.
a 2mm thick shim on the lens module was all that was needed to make it focus correctly at all distances at full bore.
 
Zorkikat,
I am really glad to see you active and discussing Russian lenses! I did not know you have 4 cats!

Well said about Jupiter-9. Putting it together if it was not marked during disassembly is almost impossible. My repairman charged double for Jupiter-9 repair, mostly because the lenses that come for CLA were worked on before and were not assembled correctly. So he would have to do this Rubik's cube from scratch.
So, to put it short - shimming the lens to work at infinity is easy, making sure it is assembled correctly internally is hard.


Здравстуйте Юрий!🙂

Great to hear from you. "Reactivated" here recently. And I have 7 cats at the moment 😀

Speaking of J-9 problems, I think it would be fair to say that the focusing issues are largely limited to the LTM version. The Kiev RF version is often hassle-free. The same could be said of the M39 and M42 SLR versions. It's an excellent lens by all means, if properly working.

One more source of problem- and related to the bad helical assembly- is the lubricant used. Old hardened lubricant is what prompts people to take apart the barrel in the first place. Cleaning and oiling requires such. And it is during reassembly where the problems start. The grease used can be too thin and make the helical threads move erratically. Heavier and thicker grease is often better for the rougher (compared to the helicals of Leica) and bigger helicals of the J-9. Heavy grease provides dampening and better grip between the threads which provide a better dampened action for more accurate focusing.

The Rubik's cube part is really hard. One J-9 took me more than a week to put together correctly. I gave up on another because it seemed intent on keeping its proper assembly position secret. I could understand why your repairman would charge that much to tinker with a defective J-9.
 
I was cheesed off initially, mh2000, but I realised soon enough that he was protecting me from possible disappointment and from having to pay for shipping both ways.
 
Fedka - good to see you here. I have heard so many good things about you, your business, and your expertise.

Hope to see you here more often if your work permits it.
 
oops, I was probably a little quick with that post... sorry. I guess I should say don't expect miracles... I just wanted a FED I camera that could be adjusted to accurately focus at Infinity and at MFD, but couldn't get one... I ended up buying a Leica IIIc to put my LTM and FSU lenses on... and amazingly it works!

🙂
 
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