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

Do not adjust the RF of the camera. The problem is the adapter. The original adapters were great, could use with all lenses. Then- the manufacturer cheapened the design. The final M-Mount version- cannot be used with the Rangefinder, and can only be used with Liveview because the company never redesigned the Cam from the LTM version to work with an M-Mount bayonet. Sad. You could adjust the Lens to line up with the Adapter. Post a picture of the adapter, I suspect it is the same one I bought.
 
SaintRF said:
I recently got an RF to LM mount adapter from aliexpress to use my Nikkor S.C 50mm f1.4 lens with my M240P. I'm having a bit of an issue, not sure if others have had this, but the mount and lens work fine, however it seems my RF patch is out of phase with this lens or with the adapter. I need to use LV to focus correctly. Now I'm trying to see if I can either adjust the lens or the mount to get it the rf patch in phase. I tested other lenses and its not the camera RF that is out misaligned, so ruled that out. The lens is an internal mount lens btw. Any suggestions would be appreciated, thanks!
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I hate to say it, but I bought the more expensive Amedeo adapter for my S mount lenses on my M 240 because the cheaper ones just don't work and can't be adjusted.

But it really really is worth it. L1000025-2.jpg

Leica M 240 w-nikkor 28/3.5
 
I use an Amedeo adapter for my Nikkor 50/1.4, Millenium version.

Pardon Our Interruption...

www.ebay.com

This is the cheap M-Mount adapter. In the Auction they state it cannot link focus to the camera, they are correct- the manufacturer did not make the obvious design change required. It can only be used for Liveview.
 
Sonnar Brian said:
I use an Amedeo adapter for my Nikkor 50/1.4, Millenium version.

Pardon Our Interruption...

www.ebay.com

This is the cheap M-Mount adapter. In the Auction they state it cannot link focus to the camera, they are correct- the manufacturer did not make the obvious design change required. It can only be used for Liveview.
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Could you just buy the cheap screw mount version that is claimed to couple with normals, and put an M adapter on it.
 
Yes- and that is what I do. The original version could be adjusted to handle external mount lenses, and internal. The later version- only can be used for internal mount, because they cheapened the design.
 
Sonnar Brian said:
Yes- and that is what I do. The original version could be adjusted to handle external mount lenses, and internal. The later version- only can be used for internal mount, because they cheapened the design.
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Well I'm glad to hear that at least that aspect works since I've got one coming this week. I have the 50 only style Amedeo for M, but have been using screw mount Leicas lately and have a couple 50 Sonnars that seem like a good match for those. The one I ordered was something like Fotofox; there was another in thread mount that did not seem to couple.
 
For $53- the adapters are worth buying and pairing with a lens.

www.ebay.com

RF-L39 Adapter For Contax Rangefinder CRF RF Lens to Leica Mount SM M39 L39 | eBay

- With This Adapter, You Can used Contax Rangefinder CRF RF Lens on Leica Mount SM M39 L39 camera body. - Although the lens will fit physically, automatic diaphragm, auto-focusing, or any other functions will not operate correctly while using this adapter. - Infinity focus is guaranteed. -...
www.ebay.com

We'll see how it goes. I can always use it on Live view.
 
Sonnar Brian said:
Do not adjust the RF of the camera. The problem is the adapter. The original adapters were great, could use with all lenses. Then- the manufacturer cheapened the design. The final M-Mount version- cannot be used with the Rangefinder, and can only be used with Liveview because the company never redesigned the Cam from the LTM version to work with an M-Mount bayonet. Sad. You could adjust the Lens to line up with the Adapter. Post a picture of the adapter, I suspect it is the same one I bought.
Click to expand...
The one I bought was this one rf-lm adapter which is the same one that got posted from ebay up there. I wouldn't have bought this one had I known the RF would be out of phase. I saw someone on a different forum post the rf-l39 one and I figured I would skip the extra adapter and go straight to the ltm one. Does the RF-L39 has the RF patch in phase? I might just buy that one instead of adjusting the lens itself if that's the case. Could use the other one for a different lens with an outer mount.
 
SaintRF said:
The one I bought was this one rf-lm adapter which is the same one that got posted from ebay up there. I wouldn't have bought this one had I known the RF would be out of phase. I saw someone on a different forum post the rf-l39 one and I figured I would skip the extra adapter and go straight to the ltm one. Does the RF-L39 has the RF patch in phase? I might just buy that one instead of adjusting the lens itself if that's the case. Could use the other one for a different lens with an outer mount.
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The only one, currently made, that I am aware of that works with the RF is the Amedeo adapter. That's why it costs more and that is why I bought it.

 
Sonnar Brian said:
For $53- the adapters are worth buying and pairing with a lens.

www.ebay.com

RF-L39 Adapter For Contax Rangefinder CRF RF Lens to Leica Mount SM M39 L39 | eBay

- With This Adapter, You Can used Contax Rangefinder CRF RF Lens on Leica Mount SM M39 L39 camera body. - Although the lens will fit physically, automatic diaphragm, auto-focusing, or any other functions will not operate correctly while using this adapter. - Infinity focus is guaranteed. -...
www.ebay.com

We'll see how it goes. I can always use it on Live view.
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I bought a slightly more expensive one since the seller claimed it couples properly with normal lenses.It looked possibly a bit better machined, though probably actually the same thing.

Mine back focuses badly enough to make it not very useful. After the first short test roll I checked four or five 50 Sonnars on well calibrated M cameras since I could use ground glass. I don't have a digital M. All were the same. I can't think of an easy way to correct this. I spent so much time checking possibilities that I didn't get a chance to quantify the error, but focus is several feet or more behind the rangefinder focused point at about 12 feet.

The sellers feedback was great when I ordered, but is now showing similar comments so I may just have to pass in on to someone with mirrorless.
 
Sonnar Brian said:
Yes- and that is what I do. The original version could be adjusted to handle external mount lenses, and internal. The later version- only can be used for internal mount, because they cheapened the design.
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@Sonnar Brian -- do you know if the 50mm-RF-coupled Contax to M39 adapter that can be adjusted for external mount lenses is still for sale somewhere and where to find one? Thanks!
 
The version that can rotated to bring the external mount in to alignment looks exactly like the newer one that does not move, both sold by the same seller and by the same manufacturer.
 
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Sonnar Brian said:
The version that can rotated to bring the external mount in to alignment looks exactly like the newer one that does not move, both sold by the same seller and by the same manufacturer.
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Brian, I mentioned earlier that my new adapter back focuses quite a bit. Is there anyway to remedy that?
 
Mark C said:
Brian, I mentioned earlier that my new adapter back focuses quite a bit. Is there anyway to remedy that?
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It is because the Contax focal length is longer than the Leica. If you look back on this thread, reading between the lines you will ascertain than you have to unscrew the lens unit from the Contax mount (the one on the lens) 180 degrees to bring it to Nikon RF spec in order for these generic CRF to L39 adapters to couple properly with a Leica rangefinder.

The difference between the adapter you have and an Amadeo or Kipon one is that those have a sloped rangefinder cam (what Brian calls “indexed”) to account for the difference in focal length between Contax and Leica 50mm lenses.
 
jc031699 said:
It is because the Contax focal length is longer than the Leica. If you look back on this thread, reading between the lines you will ascertain than you have to unscrew the lens unit from the Contax mount (the one on the lens) 180 degrees to bring it to Nikon RF spec in order for these generic CRF to L39 adapters to couple properly with a Leica rangefinder.

The difference between the adapter you have and an Amadeo or Kipon one is that those have a sloped rangefinder cam (what Brian calls “indexed”) to account for the difference in focal length between Contax and Leica 50mm lenses.
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Yes, but they should be right at infinity. I expected less than perfect coupling across the range.

I thought the 180 degree rotation was about the external bayonet on the revised (downgraded) version.
 
The error created by the current adapters is way past the Leica vs Contax difference. The newer versions of the adapters are simply way off as far as actual focus vs the cam goes. The latest one I bought is only good for Liveview. I decided to keep it, and dedicate it to a 5.8cm F1.5 lens.

To correct the Cam vs actual focus agreement: you need to build up the RF cam. This means building up with tape, or epoxying a thin ring to it.
 
Sonnar Brian said:
The error created by the current adapters is way past the Leica vs Contax difference. The newer versions of the adapters are simply way off as far as actual focus vs the cam goes. The latest one I bought is only good for Liveview. I decided to keep it, and dedicate it to a 5.8cm F1.5 lens.

To correct the Cam vs actual focus agreement: you need to build up the RF cam. This means building up with tape, or epoxying a thin ring to it.
Click to expand...
Thanks. That is what I figured. I hadn't thought of epoxying a ring. I seemed like mine would need about 4 thickness of the copper tape, and I don't imagine that would be durable enough with a rotating cam.
 
Sonnar Brian said:
The error created by the current adapters is way past the Leica vs Contax difference. The newer versions of the adapters are simply way off as far as actual focus vs the cam goes. The latest one I bought is only good for Liveview. I decided to keep it, and dedicate it to a 5.8cm F1.5 lens.

To correct the Cam vs actual focus agreement: you need to build up the RF cam. This means building up with tape, or epoxying a thin ring to it.
Click to expand...
Yea, the RF cam needs to extended a bit to bring the RF patch in phase. I was thinking of maybe 3d printing a small piece and attach it to the rf cam and see if the thickness is enough to bring the RF patch in phase with the LV focus. Might report back, but not sure if my cheapass printer can do it right... to be continued
 
Mark C said:
Thanks. That is what I figured. I hadn't thought of epoxying a ring. I seemed like mine would need about 4 thickness of the copper tape, and I don't imagine that would be durable enough with a rotating cam.
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If the copper tape does not hang up on the mount, it does hold up. I've used copper tape to create a close-focus correction for using a CZJ 8.5cm F2 with a Contax to M-Mount adapter. 15 years ago.
 
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