All of my lenses are convergent at infinity other than the summilux 50mm FLE2

[Derbyshire Man]

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As per the title.

What’s going on? I find it somewhat disconcerting, although infinity is infinity the lens does front focus very slightly. I did discuss the front focus in the past and hadn’t sent it back yet but this seems another issue with the way the lens is set up I suppose.  

Edited August 28 by Derbyshire Man

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[ApoVision]

Allowing to focus at infinity is now an in-app purchase. Just use the Leica Fotos app (or have Leica check the lens - mine works perfectly)

[J S H]

So, taking the rangefinder out of the equation, when you set the lens to the infinity hard stop wide open, is it actually focused short of infinity? Have you worked to identify any possible focus issues with some of your other long and fast lenses using LV/EVF to see if you can find a trend? 

[Derbyshire Man]

I’ve set the rangefinder to be accurate for the 50mm at 1-2m, when set like this the rangefinder doesn’t reach infinity (although if I put the lens at infinity then infinity is in focus). if I set the 50mm for infinity then the lens doesn’t focus correctly (I can’t remember if it front or back focuses) it also means that none of my other lenses focus correctly. With the 50mm focussed at 1-2m most of my other lenses are good (and all display infinity as infinity in the patch), the only exceptions being my new CV 90mm APO f2 (the CV 90mm 2.8 is fine) which back focuses, and a 24mm summilux which front focuses!

My point is it just surely be a mechanical thing with the lens as the patch at infinity is a mechanical thing not a through the lens thing and all of the other lenses allow the mechanism to reach infinity at infinity, the 50mm although being spot on at 1-2m will not do that. 

[UliWer]

1 hour ago, Derbyshire Man said:

I’ve set the rangefinder to be accurate for the 50mm at 1-2m, when set like this the rangefinder doesn’t reach infinity...

Did you do this yourself?  

[Derbyshire Man]

Yes, on three bodies, all respond the same, including the loan camera I currently have which I haven’t touched, the other lenses show RF convergence at infinity the 50mm summilux FLE 2 does not. 

[UliWer]

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So I‘d like to answer your question „What is going on?“:

You manipulated the rangefinder and can‘t expect it to work properly.  

[Derbyshire Man]

35 minutes ago, UliWer said:

So I‘d like to answer your question „What is going on?“:

You manipulated the rangefinder and can‘t expect it to work properly.  

What a load of nonsense, did you forget to actually read the last post? Not only is this the case for the ones where I have adjusted perfectly for the 35mm summilux, 28mm summilux, 21mm SEM, 40mm summicron C 40mm and a couple of others lenses AND the loan body from Leica which I haven’t touched matches those exactly, the 50mm summilux works on none; neither the ones I already had or the factory fresh when every other lens does but yes, of course, it’s the user not the product, that is just about peak LUF!

Good grief! Are you for real?

[Stuart Richardson]

On 8/29/2025 at 8:23 AM, Derbyshire Man said:

I’ve set the rangefinder to be accurate for the 50mm at 1-2m, when set like this the rangefinder doesn’t reach infinity (although if I put the lens at infinity then infinity is in focus). if I set the 50mm for infinity then the lens doesn’t focus correctly (I can’t remember if it front or back focuses) it also means that none of my other lenses focus correctly. With the 50mm focussed at 1-2m most of my other lenses are good (and all display infinity as infinity in the patch), the only exceptions being my new CV 90mm APO f2 (the CV 90mm 2.8 is fine) which back focuses, and a 24mm summilux which front focuses!

My point is it just surely be a mechanical thing with the lens as the patch at infinity is a mechanical thing not a through the lens thing and all of the other lenses allow the mechanism to reach infinity at infinity, the 50mm although being spot on at 1-2m will not do that. 

Rangefinder accuracy is dependent on both the lens collimation and the rangefinder setup. They need to be paired to each other. Leica tries to pair both the lenses and bodies to a certain standard, with an allowable tolerance. Let's say you have 0 as the standard, and you can have a lens or body with up to +3 or -3 tolerance. If you have a 0 lens and a +3 body, you should be fine. If you have a -2 body and a +1 lens, you are fine. But if you have a -3 body and a +2 lens, then you are out of tolerance. A CS rep at Leica explained this to me years ago when they were still doing their professional program and I was in a similar situation. He advised that I send in my body and all the lenses, and they would match them to each other. He said this was really the main way to ensure accuracy. I don't think you would get the same answer now, given the huge service backlogs, but fundamentally, I think the answer is the same. You may be able to find a third party repairer to do this for you. Or, if you are mostly concerned with the one lens, you can send your body and the lens with the instructions that the body focuses well with your other lenses, but you would like the lens paired to the body. Make sure to tell them that, or they might just adjust the body to the lens, throwing all your other lenses off. 

As bodies have become higher and higher resolution and lenses sharper and sharper, this has become more visible. It is one of the reasons why M development is constrained...it is very difficult to achieve mechanical (and even visual) accuracy on 60+ megapixel digital with razor sharp lenses, based on a focusing system from 1954. It is possible, but everything has to be in near perfect tolerance. 

Edited August 30 by Stuart Richardson