This might be a very stupid question, but why is not replacing the leica r-mounting plate with a 0.5mm thicker nikon f-mount plate/adapter more common? Are there any difficultuies I don't realize here?
I took a look at the underside of a Leica R mount, which a Leica serviceperson said they all were pretty much the same. If the question is to replace the Leica mount with a duplicate for another camera, then there are all sorts of extra machining under there. The grooves and ball bearing for the aperture click stops are there and very thin side walls which dictate stainless steel for strength. Just for starters.
It's been done, I've seen a 50mm Summicron-R converted to Nikon F mount just this way. The owner of leitax.com told me a few months ago that a conversion kit was a few months away. There are a few complications because on older versions the R mount and the rear light baffle attached to it combined with the metering cams are responsible for keeping the aperture ring from running past the lens' limits, i.e., if the lens has an aperture range of f/2.8 to f/22 the flange & baffle stop the aperture ring at the f/2.8 and f/22 ends of its run. The exact configuration varies depending on the lens' aperture range.
There is also a newer version of the mount with a more modular lens construction. These can be identified by the number of screws appearing to hold the flange to the lens. Six screws is the older construction while ten screws is the modular construction. In the modular construction four of the ten screws attach the flange/aperture ring assembly to the barrel of the lens:
http://wildlightphoto.com/leica/4screws.jpg
http://wildlightphoto.com/leica/apart1.jpg
The only mechanical connection between the aperture ring and the diaphragm is this lever:
http://wildlightphoto.com/leica/apart2.jpg
I'd imagine that an enterprising electronic/mechanical genius could make a replacement flange/aperture ring assembly with an aperture control motor that would interface with the camera body's electronics giving electronic aperture control of the R lens on whatever body it's on, C or N.
I just checked my Leica Rs and it doesn't look that bad. Looking at the picture on this thread it looks like the Leica mount will come off. All I have to do is cut the Leica mount off and shave the mount down by 0.5 mm. Then put a M42 to Nikon adapter on top of shaved Leica mount. They are probably 1.6 mm screws so that is not impossible to get.
I can't justify modifying them yet because they fit in my 5D without any work right now.
I'm looking at a few 90 2.8 elmarit's, I guess that is the way to too. They go for about 250-400 usd at fleebay. Get the leica mount off them, shave off enough to get infinity (shave, test, shave more, test...) and gogo? :P
ulrikft wrote:
I'm looking at a few 90 2.8 elmarit's, I guess that is the way to too. They go for about 250-400 usd at fleebay. Get the leica mount off them, shave off enough to get infinity (shave, test, shave more, test...) and gogo? :P
Are you forgetting the dimples in the back of the flange for the aperture click stops? Far better to shave a $$ adapter than a $$$ lens IMHO.
telyt wrote:
Are you forgetting the dimples in the back of the flange for the aperture click stops? Far better to shave a $$ adapter than a $$$ lens IMHO.
Good point, the thing is that all the nikon adapters I have gotten so far are quite thin to begin with, but 0.5mm shold be possible.
The idea is to put a mount on the existing mount that will be 0.5 mm below the existing flange depth. Since the new mount need to sit on the old mount shaving of the old mount is unavoidable. You have to leave enough material on the flange of the new mount to bolt through.
ISO1600 wrote:
man, go buy a busted up R4 or something, and rip that stupid mount off.
(directed at R10)
I'm not talking about a source for the Leica mount. That is even easier than your suggestion - you get them new as spare parts for a reasonable price directly from Leica in Solms here in Germany).
What I meant was whether anybody has experience with replacing the mount on a Nikon body?
R10 wrote:
... anybody has experience with replacing the mount on a Nikon body?
Professional Camera Repair in New York City, Marty Forsher's former business, did one F2 conversion that I know of. As far as I know the company is no longer in business.
Please don't forget to document your work, I know I usually do exactly that in the heat of the moment.... Hehe... It helps other crazy people like yourself a lot!
I've seen some more examples of Nikon F-mount camera bodies having their original mount replaced by a Leica R than the ones mentioned here, I'll see if I can find the original links.
I'll try to document it as well as I can, I have put a bid in on a semi-broken 90 2.8 now, if I get that for the price I want, I'll try to get the conversion done as soon as possible and get pictures of all parts of the process