Focussing question for Summaron 35 / 3,5 LTM.

arotron473

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I recently acquired a screwmount Summaron 35 / 3,5 in very good condition to use it with a Leica M2.

I have matched it to the correct Leica LTM to M adapter.

So, I have a problem / question:

When I try to focus to a quite close object the "alignment movement" of the rangefinder patch stops a lot before the focusing stops to its indicated close focussing end (1m). Actually, the lens is focussing down to about 1,7m and after this point there is no interaction between the rangefinder and the lens.

This happen to both Leica M2 and a Leica CL.

Could this be a defeat of the lens or it is something normal?

Any information would be really appreciated.

Thank you.
 
Sounds like something is blocking the movement of the cam-follower on the camera. Check the back of the lens with the LTM adapter on and see if there may be any part of it that is blocking the RF cam follower.
 
Is it possible for you to show a photo of the rear of the lens with adapter on, at 12 o'clock, and lens set to 1m ?

It's either the lens or adapter, if you successfully use the cameras with other lenses.

Roland.
 
I was going to say the exact same thing. Post a photo if possible.
There are several versions of this lens for both LTM and M mount and "convertible" between the two. The differences in the mounts themselves will make it difficult to diagnose the issue without seeing a photo.

Phil Forrest
 
...Actually, the lens is focussing down to about 1,7m and after this point there is no interaction between the rangefinder and the lens...

Try this:

1. mount the lens and adapter
2. focus to minimum distance on the lens
3. unscrew the lens leaving the adapter mounted on the body
4. move the camera toward and away from a target subject and see what distance the body focuses to without the lens.
5. removed the adapter from the body
6. repeat step 4.

If the distances focused to in step 4 and step 6 differ then the issue is with the adapter. A fault in the adapter could prevent the cam follower in the body from traveling to its full minimum focusing distance position. A fault in the body could cause the follower to contact the adapter, but this is rather unlikely in your case since the same problem occurs with two bodies.
 
Here are two photos of the lens with and without the adapter, focussed to 1m and a photo of the adapter itself.
 

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I have to add that I tested the lens on these two bodies with one more adapter- a generic one, for 50mm lenses- and the result was exactly the same...
:confused: :confused: :confused:
 
The problem, as you can see in the photos, is that the cam follower cutout on the inside of the LTM adapter is not lining up with the cutout on the lens mount. I used your image and quickly illustrated here. The cam follower is stopping at 1.7m because the back of the lens, the cam surface, is below the lens mount itself.
You can fix this with some light grinding of the lens mount in order to bring the cam relief cutout section in line with the LTM adapter. If this is not an option, you will have to find different adapters with slightly different thread entrance angles & match one up to your lens specifically. There's no way to do that but test the adapters on the lens.

sumaron_with_adapter2.jpg


Phil Forrest
 
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A rare accident that a Leitz adapter does not correctly mate with a Leitz lens. I have had two 3.5/3.5 Summarons and both worked perfectly on M bodies.
 
It seems that it is not a fault of the adapter, but of the lens.

Is there any way to readjust the way that the lens mounts on the adapter, just to take the correct position?
 
Like Phil says. That's a tough one, and should not happen with the Leica adapter.

Are you sure you screwed the lens all the way into the adapter ? When the lens is on the camera, can you tighten a little more ? What Phil indicated with yellow, has to be at 12 o'clock.

Otherwise, since you tried a second adapter, the only real solution is grinding of the lens. Maybe you want to have a pro look at it.

Sorry,

Roland.
 
I wonder if the lens was CLA'd and reassembled incorrectly. The chance of getting two faulty adapters would be pretty high, in my opinion. I still think you should give Sherry Krauter a call. You would not have to pay for a full CLA and the adjustment may not cost much. Sherry will return the lens to factory specifications.
 
The problem with adjustment is that it will make your infinity lock farther counter-clockwise (when looking at the camera. The focus tab will be at infinity near the bottom of the camera and close focus will be just about the level of where your fingers start to intrude on the finder. Can you post a photo of the lens from the front/side? I'm curious as to which version you have.
Since it's an old lens, there are any number of things which could have happened over the last 50 years. This includes someone changing out the mount for a different one during a lens repair.
If I were in your shoes, I'd have already taken my dremel tool to the back of the mount and would be shooting with it. the 35 Summaron, in all flavors, is one of the best lenses Leica ever made. What we do know is that you don't have an f/2.8 model which are a bit rarer, so use of a grinding tool isn't as touchy a subject.
There are a few here on RFF that can help you with the operation if you want to do it.
Good luck!
Phil Forrest
 
I am uploading some more pictures of the subject: M2 with the lens focussing to infinity (locked), M2 with lens focussed to the point that the rangefinder stops responding and a closeup of the lens focussed at the same distance (~1.7m)

And some news. Not sure if they are good or bad:

I checked the adapter with another screwmount lens (Jupiter 8). Of course the framelines are not the correct ones, but the focussing functions just fine...

And second, but more important, I've just developed a test roll of Neopan 1600 with this lens, used with different aperture settings and different focussing distances (in the range that works well). All the photos are super-sharp and contrasty!

At least, optically the lens seems fine.:)

Thank you again for your responses.
 

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It looks like the possibility of a "ham fisted" repair may have taken place. Guiding the optical cells back into a focusing helical when the helical is apart is delicate and one can easily guide the wrong thread on and have the lens canted by a few degrees. I'm not SURE of this without seeing the lens, but I'd say that the rotational distance between where the lens mount (with cutout) is and where it should be is probably 2 helical threads off. This would allow your lens to be focused to infinity just fine but the alignment with the camera would be wrong giving you the problem you're experiencing.
I'd say for a very quick and inexpensive solution, send it to Youxin Ye (if you're in the US). He'll have it done in a few days and the lens will be good as new. Probably run you about $50. Sherry is amazing, but as a result, she's also extremely busy and work can take a while to get done. It's worth the wait if we're talking about getting an M body repaired, but for a simple lens, Ye will be amazing. He had my IIIf CLA'd, new beamsplitter and shutter curtains done in one day turnaround. The camera was perfect!
Good luck.
Phil Forrest
 
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