Adjusting Leica M2 rangefinder?

[acjeske]

Hey all--my M2 needs a horizontal rangefinder adjustment. I've done this before on other Ms, using the 2mm allen key. My M2, though, has a very shallow slot where I expected the allen key to go in (on the arm inside the lens mount). Is there a special tool for this?

I'm on the road and trying to do research, so I'd appreciate it if anyone has a quick link or tip!

Thanks!

 

[KoNickon]

I don't know if there is a special tool or not. But I have actually found that a knife with a thin, rounded blade tip works well since the rounded tip enables you to engage the slot at an angle. Think of a table knife or, even better, a short rounded blade such as is found on spreaders for dips, condiments etc. Maybe there's a restaurant you can ask to borrow such a knife from?

Now, that said, I think that when you remove the bottom of the camera, there's a way to get direct access straight up from below, so you can use a long thin-bladed screwdriver. I can't recall if there's an access screw that comes out from the plate where the shutter adjustment screws and nuts are, or if you have to remove that plate entirely. I am sure others can answer this more knowledgeably.

 

[Rob-F]

Are you two talking about the same thing? The thin rounded blade tip sounds right for the eccentric cam on the roof of the lens chamber. I've never done the vertical adjustment, which on an M2 is behind the screw just left of the frameline illuminator window; but I'm guessing that the 2mm allen key might be the right tool for that. if that is where the 2mm wrench goes, it's not in the lens chamber, though.

 

[KoNickon]

He said "horizontal adjustment" so I assumed that was the same as "infinity adjustment," which is adjusted by the eccentric cam you mention.

 

[Phil_F_NM]

When performing this, make sure you have a lens that is in known perfect infinity calibration or else you're just going to go 'round and 'round in circles trying to get it right.

Phil Forrest

 

[Bill Blackwell]

https://www.google.com/search?q=how+to+adjust+the+rangefinder+in+a+leica+m+camera&rlz=1C1GCEA_enUS846US846&oq=how+to+adjust+the+rangefinder+in+a+leica+m+camera&aqs=chrome..69i57j33i160j33i299.36728j0j15&sourceid=chrome&ie=UTF-8#kpvalbx=_j87xYPKUHYLx-wTS2a3gBQ49

 

[Rob-F]

He said "horizontal adjustment" so I assumed that was the same as "infinity adjustment," which is adjusted by the eccentric cam you mention.

Right, my point was that the OP mentioned an Allen wrench, but I'm not aware of needing one for horizontal or infinity adjustment. So I suspected that an Allen key might be for the vertical alignment; and therefor not needed for the adjustment the OP has in mind.

 

[acjeske]

To catch up a bit here…I don’t need a link to Google, I’m here because I can’t find an answer to my specific M2 question, thanks. The horizontal is what I’m trying to adjust. The long screwdriver approach might work. What I’m getting at is there is a slot rather than an Allen head here: https://imgur.com/gallery/GxSgYfA

 

[Rob-F]

Yes, there is a slot in the eccentric cam located on the roof of the lens chamber. It is a for a flat blade, but not for a phillips. But since there is no room to use a conventional screwdriver, you need something thin and flat with its edge at an angle, say 45 to 60 degrees from the direction of insertion. A ten cent screwdriver ground off at such an angle would be fine.

 

[Rob-F]

The adjustment is not done by turning the screw by a large amount. Rather, it is done by nudging the screw without the intention of turning it perceptibly. I use a radio or television tower a couple of miles away as my infinity reference. They are very easy to align accurately with the split image rangefinder, because the structural members are thin and painted to contrast with the sky color.

Set the lens on infinity position and note the degree of error. take the lens off and gently nudge the slotted eccentric cam. Put the lens back on. Better or worse, now? If worse, take the lens off and give two nudges in the opposite direction. Put the lens back on and check your progress. It may take several iterations before it's perfect.

Use the furthest away target you can focus on precisely. Some insist it must be very distant. Some people use the moon. I feel that a radio tower a couple of miles out is fine. Just so long as you don't use a telephone pole one block away.

Persevere with it; you will get it and you will feel like a highly qualified Leica technician!

Just take the lens off right now and look up into the top of the chamber. You will see it. It's right in front.

 

[Retro-Grouch]

Do exactly as Rob-F says. The first time I did this adjustment, I was terrified, using a common cheap screwdriver on a Leica! Now it's old hat, and yes, I feel like a highly paid Leica tech. Tolle!