Question about M39 to M adapters and Jupiter lenses

[rpavich]

Ok, so I have a jupiter-8 lens and bought a cheap fotodiox adapter.

I noticed a few things. It was back focusing about 1/2" and the markings weren't lining up at all with where they should be when it was mounted.

So, (after accidentally breaking it) I purchased a second Jupiter-8 lens and another fotodiox adapter and the same thing is happening; back focus and this time the markings are way off and the lens adapter won't even lock onto the camera.

I noticed on both adapters-to-lens interface there is a gap; i.e. that the lens doesn't seem to be seating 100% against the adapter. I'm not sure how significant this is in light of my problems. It would seem that they are connected.


So to my question: Camera quest has adapters that are top notch but they are expensive; 79.00 each. I don't want to buy one and find out it fits and works the same as the 12.00 ones.

Anyone know in advance if that adapter will fix my problems or barring that, anyone know HOW to get this rig working right?


The horizontal arrows are where the gap is and the vertical arrow is marking how offset the red lines/dots are on the lens.

 

[mdarnton]

Russian lenses should back-focus on Leicas. It's not the adapter's fault. Some lucky people may have lenses that have been adjusted to work on Leicas, but the thing I most often notice is that the people who say the combo is just fine often don't know a focused photo from an unfocused one, and don't count on them to recognize that themselves, so reader beware. At longer distances or smaller openings the problem is much less obvious, so many people never have a problem.

http://www.dantestella.com/technical/compat.html

 

[rpavich]

Well I'll be darned.

That explains it.

Thanks for the info.

 

[David Hughes]

Really? Truly? Cross your heart and hope to die if you tell a lie?

 

[Huss]

The incorrectly lining up issue is the fault of the adapter. Been there, done that and I returned my Fotodiox ones. I found the same problem with Fedka adapters. And with Metabones.
The only ones that I've used with no issues are from CV (no longer available apart from on ebay etc) and Leica (same as CV). Used they will run about $40. I got mine by advertising in this site's classfieds under Want to Buy. I got a few offers so there should still be some out there.

 

[David Hughes]

Hi,

The important aspects of adapters are are that the flange between lens and body should be a nominal 1mm thick and that the correct frame lines come into the view-finder.

As for alignment, I take it that you mean the scale point at 12 o'clock? If so I'll suggest you do a little research on these forums and you'll find a lot of people talking about it and the cure. It happens to Leica bodies with Leica lenses, btw. I've a IIIc and Summitar that do it, both 1946 versions (Edit) and a Summaron that does it on my M2. It doesn't worry me as the scale is seldom looked because we are talking RF's.

There is another point, all bodies and lenses deteriorate over time and you don't usually notice it until it's too late. Plus, as we don't always shoot at f/1 the DoF will cover a lot of the problem.

In your shoes I'd carry on with the lens and adapter and check the RF at infinity. If it's OK I'd then ignore the problem of alignment and shoot as usual. Of course, I may have been incredibly lucky with all my ex-USSR lenses and bodies (I've dozens) and Leica lenses and bodies (ditto).

BTW, the lenses can be shimmed if out - if needed - by most technicians, who know what they are doing, and they can check the RF is OK as well. FWIW, I've had more trouble with RF's than anything else over the last 50 years or so and only 2 duff lenses (a Summar and a Summitar); both lenses were ill treated by their previous owners and sold on...

Regards, David

 

[rpavich]

Thanks for all of the advice. I decided to just offload the Jupiter-8 lens and buy something less problematic. I guess it can be made to work with enough fiddling around but I'm not in the mood for that. I guess previously having these lenses on a mirrorless body (fuji) spoiled me and made me think that the tolerances were better than they were. 🙂

Thanks for all of the advice....appreciated.

I ended up just getting a used CV 50/1.5 LTM mount. (and ordered a decent adapter from CameraQuest.)

 

[David Hughes]

Hi,

Was it a matter of the lens not aligning with the body as I suggested?

And, the cruncher, were pictures taken with it out of focus?

I'm curious as I see it as a minor and cosmetic adjustment but I'm guessing as I'd need to dismantle a few lenses to confirm my ideas abut how they align the focusing and DoF scales. It's never worried me as, looking at a Jupiter 8 and the Summaron, it seems cosmetic and nothing else and so I don't worry about it.

My guess is that the line up is adjusted last to be a TDC and then the 3 screws (on the J-8) are tightened. Then time and use twist them out of alignment.

Regards, David

 

[Filzkoeter]

I think I've never had a single LTM lens that lined up at exactly 12 o'clock, they were always a little bit offset (lining up either around 11 or 1 o'clock). I'm talking about Leica lenses, Jupiters, Industars and Voigtländer lenses. On adapters from Leica, Voigtländer or cheap 10€ chinese ones + on LTM bodies.

And yes, russian lenses are misfocusing on Leica bodies due to the difference of nominal focal length. The russian lenses were built to the nominal Contax focal length. To unlock their full potential on Leica bodies their focal length needs to be shortened (by changing the distance of the element groups in the back to the front) and the lens reshimmed. That's the 'hard' way. The easy way is to reshim a Jupiter-8 or -3 for about 0.1mm which brings the focus in the ballpark for short to medium distances wide open. The depth of field and the Sonnar-focus shift help with infinity when stopped down. Every lens (not only the russian ones) has slight differences in focal length. Some unadjusted Jupiter-8/Jupiter-3 lenses will work better then others (the ones with a shorter focal length are nearer to the Leica tolerances and will focus more exact then those with a longer focal length). A good and/or adjusted Jupiter is a lens to hold on onto, they can be really gorgeous and are hard to come by.

 

[rpavich]

Hi,

Was it a matter of the lens not aligning with the body as I suggested?

And, the cruncher, were pictures taken with it out of focus?

I'm curious as I see it as a minor and cosmetic adjustment but I'm guessing as I'd need to dismantle a few lenses to confirm my ideas abut how they align the focusing and DoF scales. It's never worried me as, looking at a Jupiter 8 and the Summaron, it seems cosmetic and nothing else and so I don't worry about it.

My guess is that the line up is adjusted last to be a TDC and then the 3 screws (on the J-8) are tightened. Then time and use twist them out of alignment.

Regards, David

Man..I wish the RFF instant email notification thing worked. It's just luck that I came back and saw replies.

It was two things; about 1/4" or a bit more back focus.

And also it was about 9 o'clock on the rotation on my camera. The lens and adapter didn't fit well. I have the same adapter for my CV 50/1.5 and it fits flush to the lens (though about 11:00 on the clock face for rotation.)

The rotation thing I could live with but backfocusing...no. And I'm not in the mood to dismantle it. I guess it will either have to be adjusted/shimmed or used on a mirrorless body.

 

[ferider]

Wait until you get the Nokton before you sell the Jupiter. You might find that the Nokton is more back focusing than the Jupiter at F2 for several reasons, one of them focus shift.

1/4-1/2" is nothing even for a Summicron. And for 50mm lenses, slight variations of adapter thickness make _no_ difference.

Then again, it's easy to adjust the Nokton to make most adapters align at 12 o'clock, take the mount off and you'll see. You can also use Teflon tape on your 50mm ltm lens (or a sander to the adapter) to improve the alignment.

Roland.

 

[Ron (Netherlands)]

Wait until you get the Nokton before you sell the Jupiter. You might find that the Nokton is more back focusing than the Jupiter at F2 for several reasons, one of them focus shift.

1/4-1/2" is nothing even for a Summicron. And for 50mm lenses, slight variations of adapter thickness make _no_ difference.

Then again, it's easy to adjust the Nokton to make most adapters align at 12 o'clock, take the mount off and you'll see. You can also use Teflon tape on your 50mm ltm lens (or a sander to the adapter) to improve the alignment.

Roland.

+1
and be aware that there are many Noktons out there with a preferred /ideal open f-stop of F-2.8 -or was that only the case with the 1.5 CZ sonnar?-some members here may have more exprience with these

 

[rpavich]

+1
and be aware that there are many Noktons out there with a preferred /ideal open f-stop of F-2.8 -or was that only the case with the 1.5 CZ sonnar?-some members here may have more exprience with these

I've shot the nokton at 1.5 to f/4 and didn't see anything noticeable for shift, all of the focusing was well within my bad-eyes error envelope.

In fact, every lens I own (If i'm very careful) focus' great without shift. Any error is (so far) mine.

 

[kermaier]

I seem to recall reading that Canon RF lenses were deliberately set up to mount with the index at 1-2 o'clock, because on Canon bodies you could then see the aperture setting through the viewfinder. I don't have a Canon RF body, so can't check the veracity of this lore, but FWIW....
::Ari

 

[kermaier]

Also, if you like the way your J-8 draws, you'll find a close match, in a high-quality optic, if you get a Nikkor-H.C 50/2 in LTM mount. Easy to find, and often 1/4 - 1/3 the price of a CV Nokton in LTM.