Is this normal operation for Summicrom f=5cm 1:2 collapsable lens?

[LeicaDudeM3]

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Hello everyone, I recently acquired a collapsable 50mm Summicrom 1:2 for my Leica M3 (M-mount).  I noticed that when it's in the collapsed state, the collapsable part of the lens can spin freely left or right infinitely.  When the lens is expanded I am able to lock it in place with no issues.  I would have imagined that when the lens is collapsed it would not spin freely.  Additionally, when collapsed, if I position the camera lens side down, the lens will expand by itself due to gravity.  It is not secured or locked in place when collapsed.  

I was just curious of this normal for this lens.  I'm not sure if I'm being descriptive enough so please let me know if you would like me to upload a video.  I am new to the forum so I may need to make a few posts before I am able to upload or link to a video.

Another issue i noticed is that the aperture indicator dot is not aligned with the aperture readings.  Is there a way to align it?

I tried searching for answers and came up dry.  Appreciate any insight.  Thank you!

[leon_d_arc]

Not normal

[pedaes]

7 hours ago, LeicaDudeM3 said:

Hello everyone,

Welcome to the Forum.And to the world of Leica.

I think you have three options as you will not be able to fix lens yourself. If you like images from the lens, just use it as a 'rigid' lens and don't collapse it. If you are not comfortable doing that I suggest you either return lens for a full refund or send it for a full service. I personally would only go down the service route if the lens is in generally good condition, as it  will cost at least equivalent of $300.

The collapsible Summicron does not deliver the best image quality but you may like the rendering. You may get better value looking for a new or current model used 50mm Voigtlander lens.

 

Edited September 24, 2024 by pedaes

[spydrxx]

While a CLA could possibly correct the issues you pointed out (however due to age and wear on some parts it might not), I'd just try shooting with it and either deciding you can live with its eccentricities, or not.

[mdarnton]

Look at the indented tracks up the barrel. There's supposed to be a hidden-inside-the focusing-stuff spring-loaded bearing that rides in that track to keep the lens oriented properly. Either yours is frozen or more likely (I speak from experience) someone took the lens apart and realized how hard this bearing makes getting it back together right. Or they lost it while the lens was apart.

It's not a functional problem except that the aperture dot won't come up on top every time unless you intentionally turn it correctly (dot to something like 10AM from the front) before you start to lock it in place. Some earlier lenses like the 50/3.5 Elmar do this naturally. If you send it in for a CLA (which you probably should do anyway) the person who does the job may have one to replace the missing bearing. It's perfectly OK to use it as a collapsible without the indexing bearing. You're right that this missing bearing provides some friction to keep the lens collapsed.

Most of these lenses are kind of fogged up inside and a cleaning will do wonders for picture quality. It's not a bad lens after cleaning. Up to f/2.8 or so it has a characteristic soft glow like a soft focus lens that you can use to your advantage and that some people (me, for instance) prefer. Beyond that it turns into about as sharp as anything else.

If you expect modern sizzling crispness from every lens, sure, go out and spend an extra thousand bucks or so to get that, because this isn't your lens.

If you like the photos in this thread, you have the right lens:  https://www.l-camera-forum.com/topic/268173-the-view-through-older-glass/

 

Edited September 24, 2024 by mdarnton

[LeicaDudeM3]

Thank you everyone for the responses!  I was actually able to re-align the aperture indicator dot.  It's a separate ring that can be removed and is actually keyed to fit in a certain way.  I think the previous owner must have removed it and just misaligned it.  

@mdarnton that makes total sense.  I was searching online and found photos of the missing indexing bearing you mentioned.  I haven't disassembled the lens yet but I want to try and take a look to see if it is indeed missing, or maybe snagged.  

Does anyone know how to remove the front barrel from the focusing assembly?  I haven't been able to find a tutorial or anything online.  

Thanks again!

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[LeicaDudeM3]

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UPDATE!

So I was able to remove the focus assembly and found that indeed the spring loaded index springs are missing the ball bearings.  Does anyone know the diameter of the ballbearing.  Using my calipers, is appears to be just ever so slightly larger than 1mm.  

Additionally, should I apply some grease or lubricant to the ball bearing?  I think this will help keep it keep it in place during assembly and perhaps also proved some protection when expanding the lens.  (any lubricant recommendations?)

I also removed all the old felt material (man the glue is very stubborn!), I have some self adhesive felt which I was using for automotive vibration dampening which I think can work here.  I will be posting pictures.  

 

 

Edited September 24, 2024 by LeicaDudeM3

[LeicaDudeM3]

Here are the photos:

[LeicaDudeM3]

Not sure why the photos aren't loading, will try to fix

[mdarnton]

The bearings are in little holders, like the tip of a ball point pen with a spring behind the entire capsule. It's just not a ball and a spring. I'd try to score some of the originals, do it according to the original.

[LeicaDudeM3]

 

Here are the photos, had to resize them.  I thankfully have the spring and carrier, just missing the ball bearing.  Any recommendation on the size?  I order 1mm stainless bearings from Amazon which should get here this week.  Hoping they are the correct size.

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