Leica M rangefinder adjustment

[Lindolfi]

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Also check this thread: http://www.l-camera-forum.com/leica-forum/leica-m9-forum/169666-vertical-rf-alignment-tool.html

[hoppyman]

Hi Carsten, why not consider talking to the customer service people personally first to organise a meeting and zip down to Solms yourself with your gear? Face to face communication might be very helpful with detailing exactly the history and what you need to achieve.

Thanks for the Italian and Dutch addresses. Perhaps it is time for some travelling? .............

[jhild]

I adjust my lenses and bodies myself. I have a selfmade tool for the M4-M6 and the MP. I got my

knowledge from reading Ed Rommney, Tomosy and several repair manuals and finally a lot of try

and error. I do the same with my lenses, I don´t even think about sending things to Solms. The turnaround

time is too long unless you are willing to pay extra for faster service.

Basically the question is how patient are you? How long can you stand try and error? The best way to

control is film and sometims you need a lot just for checking what you´ve done.

I adjust my lenses as well, but that´s another story. Shimming a lens is easy but then you still have to

shim the rangefinder cam of the lens and that´s not so easy but possible.

Saying all this I´m not a portrait or street photter so if my lenses or bodies are off a few cm it doesn´t

matter at all.

 

Jo

[pico]

He said that Leica have in SOLMS a laser setup that is specially made for digital and its impossible to do it properly without that system.

 

Then there is a technician for Leica in New Jersey who is doing the impossible.

[bocaburger]

Remember, the film plane is behind the inner rails of the film guide. I've forgotten the distance, but the ground glass has to be something like 0.1 mm behind the rails.

 

Your thinking that the emulsion has thickness behind the rails, and that's correct, but remember that film tends to curve forward into the opening ever so slightly, less so peripherally where it's held by the pressure plate against the rails, and more so toward the middle. Setting up a film-body rangefinder correctly is a matter of striving to be as close to the midpoint of the allowable tolerance as you can. Placing the GG on the rails does just that by splitting the difference. With the digital bodies, the focal plane is just that, a plane, which is why so many older lenses that seem to be fine with film, are found to front or back focus on the M9.

[Xmas]

Hi

 

Some rangefinders dont have zero offset vertically at best adjustement. The vertical offset will depend slightly on eye position in most others.

 

You need a lens that is perfect or three precision lens simulators, for 1m, 10m and infinity. All the lenses are built to a production tolerance, not perfect...

 

You can use a laser pointer rather than eyeballing the image for 1m and 10m... It is easier to keep this coaxial with the eyepiece optic than your eye... with a simple jig.

 

You have compromised your warrenty unless you only use a Leica repair centre.

 

Noel

[Xmas]

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Your thinking that the emulsion has thickness behind the rails, and that's correct, but remember that film tends to curve forward into the opening ever so slightly, less so peripherally where it's held by the pressure plate against the rails, and more so toward the middle. Setting up a film-body rangefinder correctly is a matter of striving to be as close to the midpoint of the allowable tolerance as you can. Placing the GG on the rails does just that by splitting the difference. With the digital bodies, the focal plane is just that, a plane, which is why so many older lenses that seem to be fine with film, are found to front or back focus on the M9.

Hi

 

Not my reading

 

i) GG adds something to regisration distance

ii) film bows towards lens to subtract something from rail registration distance so the error is addative?

 

Noel

[bocaburger]

Hi

 

Not my reading

 

i) GG adds something to regisration distance

ii) film bows towards lens to subtract something from rail registration distance so the error is addative?

 

Noel

 

i) focus is on front of GG, doesn't matter how thick it is. It adds nothing significant to the registration distance.

ii) Film emulsion thickness does add slightly to the registration distance, the forward bowing does subtract, thereby more or less cancelling each other. It isn't exact of course. Some film emulsions are thicker than others, some film stock bows more than others. Focus adjustment on a plane resting on the rails is, as I said, a manner of averaging. The factory adjustment jig rests on the rails.