Nikon-F to Leica-M lens conversion with coupling ?

menos

menos

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I am interested in technical details about this topic.
Is there any user here with a Nikon F mount lens, converted to Leica M with rangefinder coupling?

Is there even a mad scientist, who has undertaken such an operation?

What are the technical details regarding the coupling?

Are there even adaptors on the marked, that could be used as a base, to employ a coupling with respective gear for the individual lens rear group movement during focussing?

For your interest - my sparkling interest in this topic stems from a newly acquired Nikon 58 Noct-Nikkor, which is simply marvelous in its own right.
The only issue, I have with this beautiful lens is the camera system, attached to the rear of the lens (read manual focussing system with a ground glass).

I am not the one, who will destroy this expensive lens in my downstairs laboratory, but would like, to learn one or the other technical detail about it.

So, shoot please …


personal notepad:

- 50mm focal length for 1:1 rangefinder movement: "Leica standard: nominal 51.6mm" (thanks Brian)
- …
 
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An F to M adapter can probably be bought on ebay, or else built using mounts taken from other adapters. I however do not know of any type of adapter for M that includes rangefinder coupling. I am also not sure how you would transfer the focus action from the lens to the adapter. Slr lenses like do not normally need to transfer their focus movement back to a body.
You should be able to easily use that lens on lots of other camera systems, film and digital.
 
If you do design a mount that can transfer the focus action (patent it!), I expect it to need to be individually calibrated for your lens. The distance that the brass cam-ring on M-mount lenses travels is always the same for a given focus change, but the glass needs to move a different distance depending on the focal length. You will therefor need to mechanically translate the larger travel of the F lens into the shorter travel of the cam-ring.
Good luck.
 
Amedeo is the mad scientist who has made a M mount lens from a Nikon lens. The 55/1.2 was his victim, but so far I haven't heard of another. Seems he might have plan for the 50/1.2.
 
There used to be someone who made M rangefinder coupled focus scales than mounted Olympus and Nikon lenses.
Sorry I can't remember who.
You still had to transfer the scale distance on to your SLR lens.

The next leap would be to make a tie between the scale adapter and the SLR lens focus scale ( assuming they both turned the right way )
and mill/file the focus cam on the adapter to track.
 
SLR-lenses can be coupled. There are, however, several limitiations and problems. Apart from the fact, that the 'Auflagemaß' (Distance of optical group to the film plane) must be accounted for, the linear movement of the optical group along the optical axis must be equal to that of the Leitz lenses, otherwise a correct RF coupling is impossible. The last problem is the RF-coupling (transfer of the movement of the optical group to the RF).

Shot of the transfer unit on my Miranda-to-M-Adapter. I don't know who fabricated this, it looks like home made, but works quite well with my 1.4/50.
 
jbr said:
the linear movement of the optical group along the optical axis must be equal to that of the Leitz lenses, otherwise a correct RF coupling is impossible.
Click to expand...

Note that the original poster wanted to use a Noct-Nikkor for this. It's an 58mm lens, so the focal length is different from the 51.6mm of the Leitz rangefinder mechanism. It would require complex mechanical adaptation such as a sloped rotating cam.

Since the OP already stated that he doesn't intend to modify his lens, in practical terms it's all but impossible.
 
Very interesting input so far - keep the infos coming ;-)

The adapters with coupling and scale were sold by Cameraquest according to this site:

http://nemeng.com/leica/017e.shtml
quote:

"3rd party lens onto Leica M with focus coupling

Back in November 2004 Cameraquest used to offer rangefinder focus-coupled SLR lens mount adapters for $US 325.

They were claimed to work with SLR lenses from Nikon, Leica R, Olympus OM or Contax/Yashica (RTS). Focusing required a two-step process: first you focused using your rangefinder and the focus ring on the lensmount adapter, and then transfered the distance value by hand to your SLR lens. Regardless of lens focal length they always brought up the 50mm frameline.

AFAIK this adapter ring is no longer available new, although you may be able to track one down second hand."

JBR - interesting, you have more images of the device ? Which lens exactly?
More people, who have seen or used or still own M-mount coupled SLR lenses with technical details?
 
I bought an adapter similar to this one, and so far have used it uncoupled with the Nikkor 24/2.8. I plan on making an RF coupling for the 50/1.4.

http://cgi.ebay.com/Adapter-Nikon-N...87418866?pt=Camera_Lenses&hash=item4aa47fccf2

Making a coupling for a Nikon 50mm lens is straightforward, most of the 50's are actually made to the Leica standard: nominal 51.6mm.

The 55mm and 58mm Nikkor lenses can be mode to focus reasonably over a limited range, special use as portrait lenses. The focal length difference is too large to allow use without an Indexed cam. To solve that issue: you could make an adapter with a helical built in, essentially a focus mount. The helical could either rotate the Nikon lens and use an indexed cam, or incorporate a transition stage as found in telephoto lenses. This will require custom machining. The Black Jupiter-8 is a cheap lens to play with for such an approach. The Cam rotates with the lens, and although it is not indexed, an index could be cut into it. I'll have to measure the length of the J-8 focus mount, determine how much of the J-8 focus mout would have to be cut.

attachment.php
 
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In the last few months a Californian ebayer was offering for sale various Konica and Nikon slr lenses converted to M including rangefinder coupling - but not a removable adapter or reversible. Included Hexanon 57mm f1.2, 50mm f1.4, 35mm f2.0 and a couple of Nikkors - cost about $400 plus lens.

Danny
 
Brian, thanks a lot for the heads up ;-)
I will follow this topic closely.

At the moment, I am collecting infos and ideas, to see, if it is possible, to properly convert the lens (I am thinking on a semi permanent solution, exchanging the Nikon F-Mount, but not altering the lens' internal construction for the sake of resale value as an original F Noct-Nikkor).

I have had played with a F-M mount adapter today and found, that there is really very, very little space around this huge back element of the Noct.

Unfortunately, I could not mount, nor measure the items, as the seller was pretty worried about his 150,- EUR German made adapter ;-)

I am thinking about a focus range of 0.7 − 50m if this should be not possible with the 58mm focal length, I fantasize an externally adjustable RF tab within the lens mount, to basically get a dual range focus lens mount (sounds pretty undoable with proper precision for the thin f1.2 dof).

I also follow the other "can't focus 55 1.2mm lens to infinity thread" great info there as well.
 
I have one of those for my Olympus OM.

157017107_guJS5-M-1.jpg


Works reasonably well, but I wouldn't use it for a fast 50 or longer. The manual alignment wouldn't be accurate enough, I feel.

Roland.

menos said:
Very interesting input so far - keep the infos coming ;-)

The adapters with coupling and scale were sold by Cameraquest according to this site:

http://nemeng.com/leica/017e.shtml
quote:

"3rd party lens onto Leica M with focus coupling

Back in November 2004 Cameraquest used to offer rangefinder focus-coupled SLR lens mount adapters for $US 325.

They were claimed to work with SLR lenses from Nikon, Leica R, Olympus OM or Contax/Yashica (RTS). Focusing required a two-step process: first you focused using your rangefinder and the focus ring on the lensmount adapter, and then transfered the distance value by hand to your SLR lens. Regardless of lens focal length they always brought up the 50mm frameline.

AFAIK this adapter ring is no longer available new, although you may be able to track one down second hand."

JBR - interesting, you have more images of the device ? Which lens exactly?
More people, who have seen or used or still own M-mount coupled SLR lenses with technical details?
Click to expand...
 
anyone tried Novoflex?

anyone tried Novoflex?

i see Novoflex make all kinds of lenses to fit in leica m body.it is really interesting to me.and i do want to buy a OM to M and a F to M ring.but i still wonder how it can still do the focus mechanism.anyone here tried one?
 
@ Roland - more details please on the conversion ;-)

@Joe, there are some fast SLR lenses, that are not really bigger than the fast RF lenses @ f1 or f1.2 (look at the Canon 0.95, the 50 1.2 Hexanon or the Leica Noctilux).
So finder blockage is quite similar ;-)

@torchiam - the adapter I looked at today was actually from Novoflex. It seemed reasonably made regarding quality, but I don't really "see" the price of 150,- EUR, the dealer was asking today for this adapter, when some of these go for 60 USD on ebay (albeit potentially with less precision, etc…).
For a mount conversion with involved machining, I won't scavenge a 150 EUR adapter ;-)
 
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