Inexpensive Chinese Contax Mount to LTM- Maybe a little work required.

The Helios-103 is a nice lens. And if I recall correctly mine has the rear element screwed in all the way as well. So this would be normal.
The whole lens assembly can be moved in and out of the housing. There should be shims there. At least that's how it was for my 1983 Helios.

One thing of note though, if you use it on a Nikon RF - you can have the rangefinder either match infinity or close up, but not both. The focal length is different from that of Nikon lenses.

This means a Helios-103 set to match at infinity will back-focus close up.
And a Helios-103 set to match Nikon RF at NFD will never quite reach infinity. Just something to note.
 
The earlier (1981~1982) used a secondary shim for the rear groups. I shortened the shim to achieve the same results as moving the entire barrel out on others.

Helios-103 and Menopta images on the Nikon RF's.

1982 Helios-103, secondary shim shortened ~0.3mm.
got_chocalate_milka.jpgnikki_talking_icecream.jpgsuncatchers_f4a.jpg

And Helios-103/Menopta with entire barrel moved out.

dist_wide_open.jpgdistance_f4.jpgmenopta_wo_2a.jpgmenopta_wo_a.jpgnikki1_menopta_a.jpgnikki7_menopta_a.jpgnikki10_menopta_a.jpg
 
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@Sonnar Brian -- so you are getting close up to infinity with the shim mod? I imagine that this would be the same with unscrewing the barrel -- or is it different? I just want to make sure that I am understanding @TenEleven and you correctly.

My lens is a 1982 model and has the relatively thick shim. I am just still confused regarding why my copy's rear mount was not screwed all the way in before it was screwed down. But maybe looking at it through a digital M may help clarify things.
 
Moving the rear group in towards the front group produces a slightly shorter focal length for the lens, and it moves the optics farther from the image plane.

I get close to infinity with the modified lenses. You can always stop down to f2.8 or F4, focus shift will push towards infinity.
 
Hello. Can I use contax rangefinder zeiss lens on FED-2 with fotofox Contax RF-L39 adapter? or is there any better adapters around? thanks you for your times
 

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Hello. Can I use contax rangefinder zeiss lens on FED-2 with fotofox Contax RF-L39 adapter? or is there any better adapters around? thanks you for your times
 

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Hello. Can I use contax rangefinder zeiss lens on FED-2 with fotofox Contax RF-L39 adapter? or is there any better adapters around? thanks you for your times
Welcome to the forum. There are better adapters- but cost Six times as much.
I moved your post to this thread, which is specific to the adapter.

Using this to adapt a Sonnar to a Fed or Zorki: I tested my adapter with a Zorki 3M and it worked.
The RF Cam of the adapter is thinner than a J-8 and J-3, but is placed in such a way that the RF pickup of the Zorki picked it up. This is not always true of using lenses made for a Leica on a Fed or Zorki. For example: the Nikkor 5cm F1.4 jammed on the RF pickup, but the Nikkor 5cm F2 worked correctly.
 
Thank you for your time and help. Which adapter you used specifically?
I used the Fotofox adapter- the same one you posted the image of.
I've bought 5 of them. Cheap enough to dedicate to some favorite lenses.

A very early Sonnar that I had to make a custom mount for- on my M240, focus using the RF.
M2405591.jpgM2405593.jpgM2405602.jpgRIMG0029.jpg
 
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Not really because you are basically undoing what the adapter is doing (translating a 52.4mm lens standard to 51.6mm which Leica and its copies use) by using a Russian camera which follows the Contax rangefinder standard (of 52.4mm) already. I am not aware of any adapter that is Russian RF to Contax mount while having 1:1 focus travel needed.

Why not use a Russian Jupiter-8M or Jupiter-3? If you're gonna use a FED-2 these lenses will work well with it. And they are Sonnar lenses - with the early ones made from the same tools that Zeiss Jena used.

Yes, there are some samples that have been messed up - or never worked right in the first place, but that is true for vintage Contax lenses as well so you're not escaping that either way.

Also, just FYI, the picture says "Jena T" lens when it's very clearly a Carl Zeiss opton (west German) lens. Beware of fraudulent sellers. Jena (east German) lenses are often worth more so they like to "acccidentally" mislabel Carl Zeiss Opton lenses (which are still good!) as Jena ones. They however look very different and also render quite a bit differently with the Jena lenses generally giving a more "vintage" look.
 
I was not aware that the adapter is 1:1 - that's cool. So yeah go ahead and use Contax lenses on that FSU gear then. I guess the cheapness is a benefit in this scenario
 
Well. I got one of those inexpensive adapters Contax to LTM. Not sure if it was a success...will need some additional investigation.
Adapted my J-8. Weird results. It might be the lens so I'll withhold judgement until I can try another lens on it.
What's wrong? Focus is certainly off, but there's more going on...best I can describe is it seems more like someone reassembled it incorrectly.
The adventures of RF.
 
Would be good to know if infinity focus is already off. I mean if the starting point is already bad then the focus behavior can only get worse from there.

Also as per Brian's statements the cheap adapter does not adjust for the focal length difference between Contax <> Leica. So even best case it will be like using a (well calibrated) LTM Jupiter-8 on a Leica.
 
Well. I got one of those inexpensive adapters Contax to LTM. Not sure if it was a success...will need some additional investigation.
Adapted my J-8. Weird results. It might be the lens so I'll withhold judgement until I can try another lens on it.
What's wrong? Focus is certainly off, but there's more going on...best I can describe is it seems more like someone reassembled it incorrectly.
The adventures of RF.
Test the rangefinder coincidence at Infinity, and check actual focus. I used the M240 for this. One of the Three adapters I bought for $55, advertised as "does not couple with rangefinder"- the RF cam was too long by a small amount. I polished it down using a 3M fiber optic connector polishing sheet. The other two adapters were spot on for using Nikon S-Mount lenses on a Leica.
 
I don't have time to describe the behavior of my first attempt with this adapter and the J-8M from a Kiev Ive has for a while. But ... I now remember that none of the images from that kiev/lens were good and focused. Looking at what came out of the adapted lens I can see it is sometimes kind of focused at distances other than where I focused, but in some cases it doesn't seem focused anywhere and on those images where there seemed to be focused areas, it was super shallow and not "planar". I'm pretty sure this lens is either a factory dud or was reassembled wrong at some point
So ... I grabbed a couple other lenses to try instead -- another J-8M and a Helios 103. Neither of those will mount in the adapter. Not a chance. The first J-8M was a struggle to mount and then remove. I don't see how/why they won't go in, but I'm giving up on the cheap Chinese adapter. Too cheap
Just in case others were thinking of trying one out. Be prepared. I'm ok with the dud J-8M... I hate using the Kiev because I just can't do "the Contax hold". I'm hoping my other Kiev lenses are good and someday I'll find a way to use them or find someone who can.
Investigation closed.
 
So far: all of my Nikon S-mount, Carl Zeiss Jena Contax mount, and West-German Zeiss Contax mount lenses have mounted on the 5 that I've bought.
I'll try the Helios-103 and Menopta. I have had to do filing to get some of those to mount on a Nikon S-Mount camera, and even a Contax. I've shimmed nearly 20 of them for use on Nikons- starting almost 20 years ago.
 
I knew I shouldn't expect too much. I think it was the confusion of using a dud lens at first (which I think I've confirmed).

My other J8M is probably good. However I'm not sure what I would need to do to the adapter to make it accept my lens. Shimming was/is something I can do.

I'll put the adapter in the "drawer" and maybe I'll find time to mess with it later.
 
I knew I shouldn't expect too much. I think it was the confusion of using a dud lens at first (which I think I've confirmed).

My other J8M is probably good. However I'm not sure what I would need to do to the adapter to make it accept my lens. Shimming was/is something I can do.

I'll put the adapter in the "drawer" and maybe I'll find time to mess with it later.
With these adapters what I have found is that they are still adapting only FROM the Nikon rangefinder focal length standard TO the same Nikon/Leica standard only switching from the Contax/Nikon mount style to the Leica LTM mount, as Brian has detailed before. The difference between these adapters and the Amadeo Contax adapter (and presumably the Kipon and Coiro ones that are often mentioned) is that these adapters lack any accommodation (what Brian calls “indexing”) for this in the actual rangefinder cam to bring the Contax focal length to the Leica/Nikon focal length standard.

The most common solution to this in many of the Contax/Kiev lenses is to unscrew the optical unit from the mount by about 180 degrees. This is the same adjustment that Brian has described for adapting Kiev/Contax lenses to Nikon bodies.

Apologies in advance if I have bollixed this up in some way. I’m sure some expert voices will come along to assist.
 
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I’m very tempted to pick up one of these adapters to save keep my Kiev mount lenses intact as I do enjoy using them from time to time on a Kiev body.

Is there a link to it as I don’t see it ?
 
I have bought 3 from this seller:


and 2 from this one:


I suspect the latter are "seconds", I had to polish down the RF cam on one of them "slightly". I did not mind- meant I could adjust the Cam and not the lens.
The other one- perfect for my Nikon 5cm F2 on the Leica.
 
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